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+\documentclass[c]{beamer}
+
+%\usepackage{helvet}
+\usepackage{calc}
+\usepackage[utf8]{inputenc} % set your input encoding differently, if you want
+\usepackage[english]{babel}
+
+\usepackage{enumitem}
+\usepackage{eurosym}
+\usepackage{tikz}
+\usepackage{pgfgantt}
+\usepackage{amsmath,amssymb}
+\usetikzlibrary{shapes,arrows,fit}
+\usetikzlibrary{positioning}
+\usetikzlibrary{calc}
+\usepackage[absolute,overlay]{textpos}
+
+%\setbeameroption{show notes}
+
+\setlist[itemize]{label=$\bullet$}
+
+
+\def\checkmark{\tikz\fill[scale=0.4](0,.35) -- (.25,0) -- (1,.7) -- (.25,.15) -- cycle;}
+
+\setbeamertemplate{navigation symbols}{}
+%\setbeamercovered{transparent=10}
+\setbeamertemplate{navigation symbols}{\url{taler.net}}
+%\setbeamertemplate{section in toc}[sections numbered]
+
+% Adapt title information
+% =======================
+\title{GNU Taler \\ Payments for the Common Good}
+\institute{Taler Systems SA}
+\author{Dr. Christian Grothoff \& Leon Schumacher}
+\date{22.2.2018}
+
+% Some common packages
+% ====================
+\usepackage{units}
+\usepackage{amsbsy}
+\usepackage{amsmath}
+\usepackage{amssymb}
+\usepackage{graphics}
+\usepackage{epsf}
+\usepackage{epsfig}
+\usepackage{fixmath}
+\usepackage{wrapfig}
+
+
+ \usetikzlibrary{snakes}
+
+
+\begin{document}
+
+\begin{frame}
+  \begin{center}
+    GNU Taler: Payments for the Common Good
+
+%    \includegraphics[width=0.66\textwidth]{logo-2017-fr.pdf}
+    \includegraphics[width=0.66\textwidth]{taler-logo-2017.pdf}
+  \end{center}
+\begin{textblock*}{4cm}(.5cm,7.5cm) % {block width} (coords)
+  {\Large {\bf \url{taler.net}} \\
+%    IRC{\bf \#taler} \\
+%   {\small (on freenode)} \\
+    twitter@taler \\
+    mail@taler.net }
+\end{textblock*}
+
+ \begin{textblock*}{4cm}(10cm,7.5cm) % {block width} (coords)
+  \includegraphics[width=2cm]{ashoka.png}
+\end{textblock*}
+\end{frame}
+
+
+% Organization / Supplier
+
+\begin{frame}
+\frametitle{Organization}
+\begin{center}
+\begin{tikzpicture}
+ \tikzstyle{def} = [node distance= 1.8em and 1.3em, inner sep=1em, outer sep=.3em];
+ \node (origin) at (0,0) {};
+ \node (cg) [def,orange,above=of origin,draw]{CG};
+ \node (gnu) [def, draw, above=of cg]{GNU};
+ \node (pep) [def, draw, above right=of cg]{PEP SA};
+ \node (ashoka) [def, draw, above left =of cg]{Ashoka};
+ \node (ls) [def,orange,above right=of origin,draw]{LS};
+ \node (mw) [def,orange,above left=of origin,draw]{MW};
+ \node (fd) [def,orange, draw, below left=of origin] {FD};
+ \node (jb) [def,orange, draw, below =of origin] {JB};
+ \node (ue) [def,orange, draw, below right=of origin] {UE};
+ \node (ms) [def,orange, draw, right=of ue] {MS};
+ \node (bl) [def,orange, draw, right=of ms] {BL};
+ \node (pepf) [def, draw, below=of bl]{PEP Foundation};
+ \node (inria) [def, draw, below =of fd]{Inria};
+ \node (bfh) [def, draw, below =of ue]{BFH};
+
+ 
+  % grouping invividuals
+  \node[def,draw,orange,fit=(ls)(mw)(fd)(jb)(ue)(ms)(bl)](group){};
+
+  % comment right 
+%  \draw[line width=1pt,orange,decorate,decoration={amplitude=7pt,brace}]
+%  (group.north east) -- (group.south east);
+%  \node[right=of group,anchor=center,rotate=90]{Implementation partners};
+
+  
+ \tikzstyle{C} = [color=black, line width=1pt]
+
+ %\draw [->, C] (cg) -- (fd) node [midway, above, sloped] (TextNode) {};
+ %\draw [->, C] (cg) -- (jb) node [midway, above, sloped] (TextNode) {};
+ %\draw [->, C] (cg) -- (ms) node [midway, above, sloped] (TextNode) {};
+ %\draw [->, C] (cg) -- (ue) node [midway, above, sloped] (TextNode) {};
+ %\draw [->, C] (ls) -- (bl) node [midway, above, sloped] (TextNode) {};
+ \draw [<-, C] (cg) -- (gnu) node [midway, above, sloped] (TextNode) {};
+ \draw [<-, C] (cg) -- (ashoka) node [midway, above, sloped] (TextNode) {};
+ \draw [<-, C] (jb) -- (inria) node [midway, above, sloped] (TextNode) {};
+ \draw [<-, C] (fd) -- (inria) node [midway, above, sloped] (TextNode) {};
+ \draw [<-, C] (ls) -- (pep) node [midway, above, sloped] (TextNode) {};
+ \draw [<-, C] (ue) -- (bfh) node [midway, above, sloped] (TextNode) {};
+ \draw [<-, C] (bl) -- (pepf) node [midway, above, sloped] (TextNode) {};
+\end{tikzpicture}
+\end{center}
+\end{frame}
+
+
+\begin{frame}
+\frametitle{Dr. Christian Grothoff}
+\begin{itemize}
+\item Co-founder of Taler Systems SA
+\item 16+ years of experience in network security and privacy
+\item Software deployed in millions of computers and devices
+\item PhD in Computer Science, from UCLA, degrees in Mathematics and Chemistry
+\item GNU maintainer, GNU advisory board member
+\item Ashoka fellow, former Emmy-Noether scholar
+\item Lived and worked in USA, Germany, France and Switzerland
+\item Professor for network security at University of Applied Sciences, Bern
+\end{itemize}
+\end{frame}
+
+
+\begin{frame}
+\frametitle{Leon Schumacher}
+\begin{itemize}
+\item Co-founder of Taler Systems SA
+\item Co-founder of p$\equiv$p Security / pretty Easy privacy
+\item Founder of DigitalEklo
+\item Former Group CIO of Novartis
+\item Former Group CIO ArcelorMittal
+\end{itemize}
+\end{frame}
+
+
+\begin{frame}
+  \frametitle{Senior Team \hfill \& \hfill advisory board \hfill}
+  \begin{minipage}{5cm}
+    \setlist[description]{leftmargin=1cm,labelindent=0cm}
+    \begin{description}
+ \item[Leon Schumacher]\ \\ co-founder, executive
+ \item[Dr. Christian Grothoff]\ \\ co-founder, executive
+ \item[Michael Widmer]\ \\ Lawyer, executive
+ \item[Dr. Jeff Burdges]\ \\ PostDoc
+ \item[Florian Dold]\ \\ PhD Student
+    \end{description}
+
+\end{minipage}
+  \begin{minipage}{5.5cm}
+ {\tiny
+\begin{description}
+ \item[Prof. Mikhail Atallah] \ \\
+   Cryptographer, co-founder
+   Arxan Technologies Inc.
+ \item[Prof. Roberto Di Cosmo] \ \\
+   Director IRILL
+ \item[Greg Framke] \ \\
+   CIO Manulife, \\
+   former COO Etrade
+ \item[Ante Gulam] \ \\
+   Global Head of Information Security --- CISO \\
+   MetaPack Group
+ \item[Dr. Richard Stallman]\ \\
+   Founder of the \\ \mbox{Free Software movement}
+ \item[Chris Pagett] \ \\
+   former Group Head Security/ \ \\
+   Fraud/Geo Risk HSBC
+ \item[Prof. Alex Pentland] \ \\
+   MIT Media Lab
+\end{description}
+}
+\end{minipage}
+\vfill
+\includegraphics[height=0.1\textwidth]{team-images/leon-schumacher.jpg}    \hfill
+\includegraphics[height=0.1\textwidth]{team-images/christian-grothoff.jpg}\hfill
+\includegraphics[height=0.1\textwidth]{team-images/michael-widmer.jpg}\hfill
+\includegraphics[height=0.1\textwidth]{team-images/jeff-burdges.jpg}\hfill
+\includegraphics[height=0.1\textwidth]{team-images/florian-dold.jpg}\hfill
+\includegraphics[height=0.1\textwidth]{board-images/mja.jpg} \hfill
+\includegraphics[height=0.1\textwidth]{board-images/roberto-di-cosmo.jpg}    \hfill
+\includegraphics[height=0.1\textwidth]{board-images/greg-framke.jpg}    \hfill
+\includegraphics[height=0.1\textwidth]{board-images/ante-gulam.jpg} \hfill
+\includegraphics[height=0.1\textwidth]{board-images/alex-pentland.jpg}
+%\note{Advisory board still under construction.}
+\end{frame}
+
+
+\begin{frame}
+\frametitle{History of Taler Systems SA}
+\begin{itemize}
+\item Software development started at TU Munich (2013)
+\item Grant from Renewable Freedom Foudation to develop core system (2014-2017)
+\item Inria decision to create startup in (2015)
+\item Company founded 2016 by Dr. Christian Grothoff and Leon Schumacher
+\item Copyright agreement with Inria, GNUnet e.V. and other stakeholders (2017)
+%\item Swedish community member informs us about e-Krona project (9'2017)
+%\item First hire from former Inria team (2018)
+\item Core team assisted by many volunteers ($\Rightarrow$ easy to grow)
+\end{itemize}
+\end{frame}
+
+
+% ``References and experience within the field''
+\begin{frame}
+\frametitle{Strategic partners}
+\begin{itemize}
+\item GNU Taler: We are a GNU package within the GNU project
+\item Hacker community: supported by CCC, Tor project, Enigmail, GnuPG, Nitrokey, etc.
+\item Ashoka: Prof. Grothoff is part of a global network of social entrepreneurs
+\item p$\equiv$p: Taler partners with pEp for e-mail integration
+\item Roots in academia: partners at TUM (I8), Inria (TAMIS team), ETH Zurich (Helbing) and MIT (Media Lab)
+\item Roots in industry: Leon Schumacher, Group CIO of ArcelorMittal \& Novartis
+\item Roots in banking: Michael Widmer, Chief of Staff of Adecco Group; Bank Gutenberg, AIG, EUREX, Chicago Board of Trade/Eurex Alliance
+\end{itemize}
+\end{frame}
+
+
+\section{What is GNU Taler?}
+\begin{frame}{What is GNU Taler?}
+  \vfill
+  \begin{center}
+GNU Taler is an electronic instant payment system.
+  \end{center}
+  \begin{itemize}
+  \item Uses electronic coins stored in {\bf wallets} on customer's device
+  \item Think electronic {\bf cash}, with a few twists
+  \item Pay in {\bf existing currencies} (i.e. EUR, USD, BTC)
+%    or use it to create new regional currencies
+  \end{itemize}
+  \vfill
+  \begin{center}
+    Taler is {\bf not} a cryptocurrency.
+  \end{center}
+\end{frame}
+
+
+\begin{frame}
+\frametitle{GNU Taler Overview}
+\begin{center}
+\begin{tikzpicture}
+ \tikzstyle{def} = [node distance= 5em and 6.5em, inner sep=1em, outer sep=.3em];
+ \node (origin) at (0,0) {};
+ \node (exchange) [def,above=of origin,draw]{Exchange};
+ \node (customer) [def, draw, below left=of origin] {Customer};
+ \node (merchant) [def, draw, below right=of origin] {Merchant};
+ \node (auditor) [def, draw, above right=of origin]{Auditor};
+
+ \tikzstyle{C} = [color=black, line width=1pt]
+
+ \draw [<-, C] (customer) -- (exchange) node [midway, above, sloped] (TextNode) {withdraw coins};
+ \draw [<-, C] (exchange) -- (merchant) node [midway, above, sloped] (TextNode) {deposit coins};
+ \draw [<-, C] (merchant) -- (customer) node [midway, above, sloped] (TextNode) {spend coins};
+ \draw [<-, C] (exchange) -- (auditor) node [midway, above, sloped] (TextNode) {verify};
+
+\end{tikzpicture}
+\end{center}
+\end{frame}
+% Demo here
+
+
+\begin{frame}
+\frametitle{Components in Depth}
+\begin{itemize}
+\item Exchange: payment service provider
+  \begin{itemize}
+  \item Wire plugins: integration with register based system
+  \item Database plugins: persist cryptographic proofs
+  \item Auditor: verifies correct operation
+  \end{itemize}
+\item Wallet: customer user interface
+  \begin{itemize}
+  \item Browser extension
+  \item E-mail client integration (future work)
+  \item NFC payments (future work)
+  \end{itemize}
+\item Merchant: shop
+  \begin{itemize}
+  \item Front end (custom)
+  \item Backend (RESTful service, performs cryptography)
+  \item Backend database: persists cryptographic proofs
+  \item Back office Web service: access to business data
+  \end{itemize}
+\item Protocol specification (generally JSON-based)
+\end{itemize}
+\end{frame}
+
+
+
+% ``References and experience within the field''
+\begin{frame}{Hardware requirements}
+\begin{itemize}
+\item[@] Exchange:
+  \begin{itemize}
+    \item high-availablility data center (with replicated database),
+    \item expected amortized average transaction costs $\approx$ \EUR{0.000001}
+    \item transaction latency $\approx$ network RTT
+  \end{itemize}
+\item[@] Merchant:
+  \begin{itemize}
+  \item database to store contracts and cryptographic proofs
+  \item minimal CPU, hardware and bandwidth requirements
+  \item integration cost small due to reusable backend and backoffice components
+  \end{itemize}
+\item[@] Customer:
+  \begin{itemize}
+  \item database (IndexedDB) to store coins, contracts and cryptographic proofs
+  \item minimal CPU, hardware and bandwidth requirements
+  \item DesignShift estimated \EUR{300,000} cost for design of
+        mass production ready \EUR{10} NFC hardware wallet in CC format
+  \end{itemize}
+\end{itemize}
+\end{frame}
+
+
+% ``References and experience within the field''
+\begin{frame}{Availability / Reliability / Off-line transactions}
+
+  {\bf CAP theorem:}
+\begin{center}
+  Consistency, Availability, Partition-Tolerance: pick two!
+\end{center}
+\vfill
+\begin{itemize}
+\item By default, Taler focuses on consistency and detects double-spending online \\
+      $\Rightarrow$ Network partitions impact availability
+\item Sharing coins via NFC while offline in principle possible \\
+     $\Rightarrow$ Double spending detected late, receiver may be defrauded
+\end{itemize}
+\vfill
+\end{frame}
+
+
+\begin{frame}{Security}
+\begin{itemize}
+\item Each party must keep their private keys secure
+%\item Private keys are never disclosed by the protocol (not even during payments)
+\item Losses are by design with party where keys were compromised
+\item Losses are bounded to:
+\begin{itemize}
+\item amount of coins carried in wallet (for consumer)
+\item volume of transactions during compromise (for merchant)
+\item amount of coins in circulation (for exchange)
+\end{itemize}
+\item Denomination key expiration used to limit risk
+\item Exchange operator typically has escrow account matching issued coins
+\end{itemize}
+\end{frame}
+
+
+\begin{frame}{Scalability}
+  \begin{block}{By design}
+  For exchange operator:
+ \begin{itemize}
+  \item linear scalability (via sharding) of database
+  \item linear scalability of cryptographic operations
+ \end{itemize}
+ System also supports having multiple exchange operators.
+  \end{block}
+  \begin{block}{Implementation limitations}
+    \begin{itemize}
+    \item Auditor implementation is currently sequential
+    \end{itemize}
+  \end{block}
+  All components are {\em free software} with {\em public specifications}.
+\end{frame}
+
+
+\begin{frame}{Interoperability}
+ \begin{itemize}
+  \item Database layer abstracted via interface
+  \item Wire transfer layer abstracted via interface
+  \item Open protocol specification
+  \item RESTful JSON-based APIs
+  \item Designed to operate well with HTTP(S)
+  \item Recent changes to better support Apps and non-WebExtension compatible browsers
+  \item Core logic implemented in portable C code (exchange, merchant backend)
+  \item Wallet-specific logic implemented in TypeScript \\
+        ($\Rightarrow$ WebExtensions, React)
+ \end{itemize}
+\end{frame}
+
+
+\begin{frame}{Reliability}
+ \begin{itemize}
+  \item Cryptographic constructions are well-understood
+  \item Cryptographic primitives are state-of-the art
+  \item Protocols have been peer-reviewed by various cryptographers
+  \item State-of-the-art secure software development process
+  \item Implementation has been (partially) subjected to security audits, more planned
+  \item World-class information security team
+ \end{itemize}
+\end{frame}
+
+
+\begin{frame}{Anonymous transactions}
+\begin{itemize}
+\item Customer must identify when withdrawing via register system (KYC)
+\item Merchant must identify to receive via register system (AML)
+\item Merchant can be compelled to disclose terms of contract
+\item Customer can be {\em anonymous} when paying
+\item Multiple transactions of same customer are {\em unlinkable}
+\item Customer has proof of purchase
+\item Customer can voluntarily disclose identity, but not be compelled
+\item Exchange operator must be well-known and certified by auditor
+\item Auditor keys usually hard-coded in customer and merchant software
+\end{itemize}
+\end{frame}
+
+
+\begin{frame}{Identity Management}
+ \begin{itemize}
+  \item Taler provides electronic cash on top of register-based system
+  \item Typically, customer and merchants have accounts in register-based system \\
+        $\Rightarrow$ Identification piggy-backs on register-based system
+  \item Customer's wallets have a key to identify them
+  \item Possible to send electronic coins to customer based on wallet key \\
+        $\Rightarrow$ Possible to provide {\em welfare} to unbanked individuals
+  \item Receiving Taler payments requires account in register (for taxability)
+ \end{itemize}
+\end{frame}
+
+
+\begin{frame}{Accessibility}
+ \begin{itemize}
+ \item Anyone can customize wallet, as {\em protocols} enforce security!
+ \item Wallets (HW, SW) will be customized to
+       match accessibility requirements (children, disabled, elderly)
+ \item Prototype was publicly demonstrated and explained by 10 year
+       old kid at hacker conferences (videos available)
+ \item Transaction speed is one click plus network RTT
+ \item Avoiding customer authentication improves privacy and usability!
+ \item Advisory board voiced ethical concerns with payments becoming
+       too easy and need to integrate financial education with wallet.
+ \end{itemize}
+\end{frame}
+
+
+\begin{frame}{Social Impact of Taler}
+  \begin{center}
+    \includegraphics[height=0.8\textheight]{social-impact.pdf}
+  \end{center}
+\end{frame}
+
+
+\begin{frame}
+    \frametitle{Possible outcomes (optimistic)}
+    \begin{itemize}
+        \item{Replace Mastercard/Visa/Paypal online} \\
+              $\Rightarrow$ Cheaper transactions $\equiv$ 3\% reduction in VAT
+        \item{Replace cash and credit cards} \\
+              $\Rightarrow$ Faster business transactions in stores
+        \item{Income via Taler is easily tracked by the government} \\
+              $\Rightarrow$ Less corruption, less tax evasion possible
+        \item{Nobody can track how you spend your money} \\
+          $\Rightarrow$ Privacy for citizens! \\
+          $\Rightarrow$ Industrial espionage defense for business!
+    \end{itemize}
+\end{frame}
+
+
+\begin{frame}{}
+  \vfill
+  \begin{center}
+    {Why should {\em Riksbank} be interested?}
+  \end{center}
+  \vfill
+  \begin{center}
+  \includegraphics[height=3cm]{illustrations/usmint.jpeg}
+  \end{center}
+  \vfill
+  \begin{center}
+    {Why not do {\em online} what they do {\em offline}?\footnote{Just better: you can anonymously receive cash, but not Taler coins.}}
+  \end{center}
+\end{frame}
+
+
+\begin{frame}{Greatest challenges for Taler Systems SA}
+\begin{itemize}
+ \item Onboarding of customers \& merchants
+ \item Banking license \& integration with register-based system
+% \item Funding for non-proprietary (FLOSS) software to establish a
+%   payment systems commons without patents
+ \end{itemize}
+\end{frame}
+
+
+\begin{frame}{PoC project}
+ \begin{itemize}
+ \item Taler Systems SA as technological solution provider (expertise)
+ \item Riksbank as operator (escrow account, data center, RIX link)
+ \item Key steps:
+   \begin{itemize}
+   \item Agreement on costs and responsibilities for PoC (1 M)
+   \item Define specifications for small PoC / demonstrator (1 M)
+   \item Setup PoC (1 M)
+   \item Satisfy Riksbank technical security and performance requirements (6-12 M)
+   \item Identification of niche market and partners for public PoC launch (4-6 M)
+   \end{itemize}
+ \end{itemize}
+\end{frame}
+
+
+
+\begin{frame}
+  \begin{center}
+%    \includegraphics[width=0.66\textwidth]{logo-2017-fr.pdf}
+    \includegraphics[width=0.66\textwidth]{taler-logo-2018.pdf}
+  \end{center}
+  \vfill
+  \hfill A GNU package
+\end{frame}
+
+\end{document}
+
+
+\section{Comparison}
+\begin{frame}{Comparison}
+  \begin{center} \small
+    \begin{tabular}{l||c|c|c|c|c}
+                & Cash & Bitcoin & ZCash    & Creditcard & GNU Taler \\ \hline \hline
+    Online      &$-$$-$$-$  &   ++    &    ++    &     +      &   +++  \\ \hline
+    Offline     & +++  &   $-$$-$    &    $-$$-$    &     +      &   $-$$-$  \\ \hline
+    Trans. cost & +    & $-$$-$$-$   & $-$$-$$-$  &     $-$      &   ++  \\ \hline
+    Speed       & +    & $-$$-$$-$   & $-$$-$$-$  &     o      &   ++  \\ \hline
+    Taxation    & $-$    &   $-$$-$    &  $-$$-$$-$   &    +++     &  +++  \\ \hline
+    Payer-anon  &  ++  &   o     &    ++    &  $-$$-$$-$   &  +++  \\ \hline
+    Payee-anon  & ++   &   o     &    ++    &  $-$$-$$-$    &  $-$$-$$-$ {\bf (*)} \\ \hline
+    Security    &  $-$   &   o     &    o     &    $-$$-$      &  ++   \\ \hline
+    Conversion  & +++  &  $-$$-$$-$   & $-$$-$$-$ &    +++     &  +++  \\ \hline
+    Libre       &  $-$   &  +++    &    +++   & $-$ $-$ $-$      &  +++  \\
+  \end{tabular}
+  \end{center}
+  {{\bf (*)} Not having payee-anonymity is a good thing as otherwise money laundering
+    becomes a real problem.}
+\end{frame}
+
+
+
+
+\section{The Problem}
+\begin{frame}{The Problem}
+
+  3D secure (``verified by visa'') is a nightmare:
+  \begin{minipage}{5cm}
+    \begin{itemize}
+    \item Complicated process
+    \item Shifts liability to consumer
+    \item Significant latency
+    \item Can refuse valid requests
+    \item Legal vendors excluded
+    \item No privacy for buyers
+     \end{itemize}
+  \end{minipage}
+  \begin{minipage}{5cm}
+      \includegraphics[width=\textwidth]{illustrations/cc3ds.pdf}
+  \end{minipage}
+  \vfill
+    Online credit card payments will be replaced, but with what?
+\end{frame}
+
+
+\begin{frame}{The Problem}
+\vfill
+  \begin{textblock*}{12cm}(0.5cm,1cm) % {block width} (coords)
+    \begin{itemize}
+    \item Global tech companies push oligopolies
+    \item Privacy and federated finance are at risk
+%    \item 30\% fees are conceivable
+    \item Economic sovereingity is in danger
+    \end{itemize}
+\end{textblock*}
+\begin{textblock*}{4cm}(3.5cm,5.2cm) % {block width} (coords)
+ {\includegraphics[width=\textwidth]{competitor-logos/amazon.png}}
+\end{textblock*}
+\begin{textblock*}{2cm}(7cm,3cm) % {block width} (coords)
+ {\includegraphics[width=\textwidth]{competitor-logos/alipay.jpeg}}
+\end{textblock*}
+\begin{textblock*}{2cm}(3cm,3.5cm) % {block width} (coords)
+ {\includegraphics[width=\textwidth]{competitor-logos/paypal.jpeg}}
+\end{textblock*}
+\begin{textblock*}{2cm}(9cm,5cm) % {block width} (coords)
+ {\includegraphics[width=\textwidth]{competitor-logos/applepay.jpeg}}
+\end{textblock*}
+\begin{textblock*}{2cm}(7.5cm,5.9cm) % {block width} (coords)
+ {\includegraphics[width=\textwidth]{competitor-logos/samsungpay.jpeg}}
+\end{textblock*}
+\begin{textblock*}{1cm}(9.5cm,6.3cm) % {block width} (coords)
+ {\includegraphics[width=\textwidth]{competitor-logos/android_pay.png}}
+\end{textblock*}
+\vfill
+\end{frame}