Developers have reported that it is difficult to maintain applications on multiple versions of Android, owing to compatibility issues between versions 1.5 and 1.6,
especially the different resolution ratios in use among various Android phones.
Such problems were pointedly brought into focus as they were encountered during the ADC2 contest.
Further, the rapid growth in the number of Android-based phone models with differing hardware capabilities also makes it difficult to develop applications that work on all Android-based phones.
As of August 2010, 83% of Android phones run the 2.x versions, and 17% still run the 1.5 and 1.6 versions