Converting iPhone apps to iPad

OpenGL and OpenGL ES Tessellator

Tessellators and Quadrics
Polygon Tessellation In OpenGL
OpenGL Tessellation

GLU ES for OpenGL ES 1.x (for Win32)

iGLU: GLU for OpenGL ES 1.1 (for iPhone)
gluTessellator on iPhone

Anti-aliased line with Texture

How to Render Anti-Aliased Lines with Textures in iOS 4

Sharing custom data between two iPhone applications

In my iPhone application work, recently one issue came up. It is separating an iPhone application that I am developing into two applications while sharing custom data (i.e., images and text files) between two applications. So, I googled several forums with this issue. Here is my findings.

1) Using a server as a storage
2) Using a URL scheme
3) Using the pasteborad (UIPasteboard)
3) Using an "Address book" area

None of these was appropriate for my project where I need to share several images (1600x1200) and text files on a device without connection to a server. So, at this moment, I conclude that there is no way to share custom data between two iPhone applications.

[Reference 1] [Reference 2] [Reference 3] [Reference 4]

Code Sign Error after reinstalling provisioning profile

Sometimes Xcode project file easily gets messed up. For example, when I try to rebuild my application that worked well with my previous provisioning file yesterday, however I reinstall my provisioning file today. In this case, following error message can be show up;

"Code Sign Error: Provisioning Profile (long string) can't be found."

Here is an easy solution.

1) Open the project file in a text editor:
The .xcodeproj file is actually not a file but a directory, like an application bundle. So, you can right click it in Finder to open. Then, select "package contents". Now, you will see several files. The actual project file is "project.pbxproj". Open it in a text editor.

2) Search provisioning profile setting and manually erase the lines. Save the project file:
They will look like these;
PROVISIONING_PROFILE = "xxxxxx.....xxxxx";
"PROVISIONING_PROFILE[sdk=iphoneos*]" = "xxxxxx.....xxxxx";

3) Reopen the project in Xcode and go to the settings to reselect your new provisioning profile.

Android on the iPhone

Refer this blog

Using camera in your iPhone Application

Here are some of cool stuffs that can be referred for iPhone application development using build-in camera.

1. iPhone Camera Overlay App With Custom Button Example
2. Custom camera applications development using iPhone SDK
3. Custom UIImagePickerController camera view