Challenges while testing an application on different platforms

One of the biggest challenges facing the mobile games industry, however, is the sheer number of different devices, operating systems, screen sizes and local market requirements. With more than 4000 different J2ME enabled devices and several hundred Brew Devices in the global market in along with multi-language and other customization requirements from mobile operators,

J2ME Devices – a large number of vendors such as Nokia, Motorola, Samsung, LG, Philips make Java enabled handsets and less backward compability.

Brew devices- have different brand and less backward compability

In addition different screen size pixel length, keyboard, touch screen, dimension
Over 4000 os variation and more than 80 variations in carriers just collect info and guidelines

Cross platform or Intra platform porting:
J2ME to BREW, Symbian to BlackBerry, J2ME to iPhone etc.
Operator or Carrier specific porting:

Most US (AT&T (Formerly Cingular), T-Mobile, Sprint, Verizon), European (Vodaphone, Orange, Virgin Mobile etc.) and Canadian Carriers)

Inter platform porting:
Up-gradation of OS versions, new device compatibility, new features addition or enhancement, etc.

The biggest challenge is day by day growing new technologies cannot meet global criteria. Tight deadline and device and operator guidelines