March 4th – Day 3

Breakfast – Bagels and fruits.

Opening Keynotes

MediaLets – Eric Litman is the CEO of MediaLets. MediaLets is a mobile analytics and advertisement company for almost all mobile devices. Currently the company is targeting the iPhone and Android markets. Linking your application to customer interaction via analytics is key to understanding your customer base and will lead to sustaining your customer base.

Contact: eric.litman@medialets.com
Web Site: http://www.medialets.com/

AdMob – Ed Mob from AdMob. Admob is a mobile advertisement company focusing on iPhone and Android markets. To date, AdMob has severed 65 billion ad impressions, since they were founded in 2006. The iPhone is their main handset. 1 in 3 unique iPhones have viewed ads through AdMob, which is 6.5 million of the 17 million iPhones on the market. 80% of all iPod Touch users are under the age of 24 years old. This information can be useful when understanding your market and whom you could be writing your applications for. Ed walked use through how to AdMob can help you earn money for paid apps or free apps.

Contact: mfyall@admob.com
Web Site: http://www.admob.com/

Session 1: Tony Hillerson – iPhone Persistence for Mere Mortals

Tony is a Software Architech from EffectiveUI, which has recently started working in the mobile community.

Persistence types consists of settings, sqlite, fmdb (Migration Manager), or Aptiva (ActiveRecord).

Settings (System Settings) – These settings are separate from your app and are configurable through the standard Apple system settings views. You are limited to the following types: NSData, NSString, NSNumber, NSDate, NSArray, or NSDictionary.

SQLite is an embedded relational database written in C, which is default choice for DB solutions on the iPhone. SQL C API (functions): http://www.sqlite.org/c3ref/funclist.html

FMDB Migration Manager is a schema migration support for the SQLite library that uses FMDB. FMDB has error checking and has an clean API, which is more of wrapper used for saving your data to the SQLite database. No need to create prepared statements as the FMDB does this for you. With the FMDB Migration Manager you are able to create schema by scripts (or functions) and the manager keeps tracks of these changes for version controls.

Code is on github, called fmdb-migration-manager = http://github.com/mocra/fmdb-migration-manager/tree/master

Aptiva is an objective-C implementation of ActiveRecord. This framework is even more of a wrapper then FMDB, and does more of the work for you. You do not have to right any sql, only if you want to filter items. Even with the filters, you only have to pass in sql (column names) snippets.

Code is on github, called fmdb-migration-manager = http://github.com/aptiva/activerecord/tree/master

Tony walked use through his example code, GroceryGetter, which demos the usage of all four persistence types he discussed.

Code is on github, called grocery_getter = http://github.com/thillerson/grocery_getter/tree/master

Tony also mentioned that he just found out about the SQLitePersistenceObject project and recommends looking into the features. The other avenue for persistence would be to create your own home grown, but not the recommended unless you have a specific need to do so.

Contact: tony.hillerson@gmail.com (twitter: thillerson)
Web Site: http://thillerson.blogspot.com
Presentation Notes: http://www.slideshare.net/thillerson/iphone-persistence-for-mere-mortals

Lunch Session – Round Table pizza and drinks.

Session 2: Danton Chin – Managing and Optimizing Memory Usage

The simulator has an option for running low memory. When you app is closing for memory issues, you have 5 seconds to close out of applicationWillTerminate method, else your app will be killed. Reduce the size of images and plists. For PNG images, use pngcrush -iphone. As a rule of thumb, use release over autorelease. Dealloc objects when they are no longer needed. What are some tools to be used? Instruments or Shark can be used. Clang Static Analyzer or DTrace are other tools. You can use custom trace documents or templates when using Instruments. The ObjectAlloc and Leaks instruments are the most used and valuable for finding issues.

Danton walked use through the Instruments application and explained how to monitor an app in the simulator, this can also be done on a connected iPhone or iPod. He showed how to use a custom template and how to use the predefined templates. He explained some of the inspectors and how to review the items that have been leaked or the objects have been allocated.

Clang Static Analyze is a sub-project of Clang, which is a sub-project of LLVM, which was announced at WWDC 2008. Clang has multiple issues currently, because it is in the early stages of development, but this project is very promising.

Recommended book – Learning Objective-C by Scott Stevenson.