With the use of UDID developers were able to track which exact devices were accessing their apps and other confidential details. As such the UDID retrieved by a single app does not pose much danger but when multiple apps collaborate and share the UDID based information a holistic picture about the user can be generated posing much higher thread. To curb this, Apple started forcing developers to use vendor or advertising identifiers that are specific to apps. So even if apps or ads share the unique identifier of a certain device generated by itself it will still be deemed useless as they cannot combine information. Apple started rejecting apps with UDID usage in 2011 without making any official statement about it, but right now Apple seems to be quite serious about this issue as per the latest update on Apple developers site that states that all apps currently making use of UDID needs to update their apps and stop using it.
Apart from that Apple is forcing all the app developers to get their Apps to be compatible to the new iPhone 5’s 4″ display, with rumours going strong supporting the low cost iPhone, there is every possibility that by end of Summer this year there will be a severe decline in devices sporting a 3.5″ display and a spike in devices using 4″ display. Apple seems to be gearing up to showcase that majority of its apps will be compatible with its latest range of iPhones and iPod touch once they are launched in September 2013.
With the new screen size requirement set by Apple, developers will have to use iOS SDK 6 which essentially means that Apple will be curbing support for devices running iOS version 4.2 and below soon. We request our users to read the app update description carefully from now on if you are using older firmware versions.