1 Proprietary & Confidential Stephen Bourdeau Mobile Tech Lead TripAdvisor, LLC Hybrid App Development MoMo Mobile Camp, February 19 th, 2011

2 Proprietary & Confidential TripAdvisor is the world’s most popular & largest travel community with.. 40 million unique monthly visitors 20 million registered members 40 million reviews and opinions Present in 18 countries and 26 languages TripAdvisor Mobile Site and Apps 5 million unique monthly visitors We hit 1 million unique monthly visitors the month after we launched Same global coverage Native apps on a variety of platforms iOS (iPad app reached #1 in more than 50 countries) Android Nokia Ovi HP/Palm webOS … and our mobile site only launched 14 months ago (12/7/2009)! How did we get there so fast?

3 Proprietary & Confidential Mobile web app Built using HTML, CSS, JavaScript (maybe some tool kits) Pros Quick to launch and update Easier to track metrics Cons Does not have access to low level features such as camera, accelerometer, etc. Native app Built using a variety of languages such as Objective-C (iOS), Java (Android), J2ME (BB), etc. Pros Has access to lower level features Cons Higher development cost across multiple platforms In some cases (iOS) slower launch/update times due to approval process Tougher to track metrics

4 Proprietary & Confidential Then there is a dark corner where native apps are actually web apps in disguise HP/Palm webOS apps are built with HTML, CSS, and JS just like a web app but have access to native functionality Nokia Ovi does the same thing Provides access to low level features via JS Hmmm… that sounds like a good idea

5 Proprietary & Confidential Hybrid Apps combine the best of both worlds Develop the basic building blocks of the app in HTML, CSS, JS and display through a web view Build features leveraging those low level APIs natively Quick(er) to launch & update most features Easy(er) to track metrics Wrap them up together and shake well before drinking

6 Proprietary & Confidential There are many frameworks out there to help ease the cross-platform pain of native development PhoneGap RhoMobile Appcelerator Etc… So should you use them? They serve a purpose, but with limitations (still maturing, not perfect) Introduce another layer of abstraction (good and bad) Hybrid apps can be considered as an alternative cross-platform solution

7 Proprietary & Confidential There is a big debate over what the future holds for mobile Some think that native apps are here to stay MG Siegler, TechCrunch “…the fact that very few [developers], if any, choose to go HTML5-only is telling…” - Siegler Some think that HTML5 is the way to go John Ciancutti, VP of Personalization Technology, Netflix - Why We Choose HTML5 for User Experiences on DevicesWhy We Choose HTML5 for User Experiences on Devices “Our customers don’t have to go through a manual process to install new software every time we make a change, it ‘just happens.’” - Ciancutti

8 Proprietary & Confidential With a hybrid app you are free to implement whatever works best Choose the right tool for the job! Use simple HTML, CSS, JS to build the simple stuff Use HTML5 to build more complicated features and push them out cross-platform Use native code for the most complicated/low level features Entire page built with HTML & CSS Photo viewer built with DHTML/JS Photo upload built natively

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10 Proprietary & Confidential You want to spend your time building cool stuff, not reinventing the wheel for each platform (hello “Owl Cam”)

11 Proprietary & Confidential Is the web site page view from a mobile web browser or app? Android – Allows you to change your user agent iOS – Does not allow you to change your user agent But wait! In iOS the webView does have a different user agent than mobile safari. Doh… what if another hybrid app looks at your web page? Best solution we have found for iOS? A cookie (who doesn’t love a cookie?) Set the cookie on the web view every time the app opens Then there is Windows Phone 7 – doesn’t allow you to set a cookie natively on the web view But we can set it server side…

12 Proprietary & Confidential If you know you are serving a web page inside your hybrid app you can send modified URLs to perform native actions Facebook does (did?) this in their iOS API with a return to their own fake protocol: fb://do-something-useful

13 Proprietary & Confidential From within your native app most web views allow you to listen for a change to the URL iOS – UIWebView – shouldStartLoadWithRequest: Android – WebViewClient - shouldOverrideUrlLoading() Example: location services on webOS Not currently supported by the webOS browser Instead we navigate the web view to a URL with dummy values which gets intercepted by the native wrapper turns into

14 Proprietary & Confidential As an added benefit you can include a link on both the web page and native app that gets intercepted. Remember that link to launch a native photo upload? If viewed from a mobile browser it gives a promo to download the app… have your cake and drive app downloads too!

15 Proprietary & Confidential Some platforms allow you to execute JavaScript against the web view Place data in the page you return from the server in JavaScript variables On page load pull out the data with the native wrapper and put it to good use WebView loads and contains location pin data in a JS variable Pin data gets pulled out and rendered natively

16 Proprietary & Confidential Stephen Bourdeau Mobile Tech Lead TripAdvisor, LLC Questions?

17 Proprietary & Confidential Hiring like crazy! Lots of interesting mobile projects in the pipeline Lots of interesting social projects in the pipeline (what could you do with 1.2 billion geographic place pins from our Facebook users?)