I have to disagree with you. It is not just about effort. It is also about opportunity cost. Imagine you work for someone else and then you tell them that for

I have to disagree with you. It is not just about effort. It is also about opportunity cost. Imagine you work for someone else and then you tell them that for the kind of UI we want I can ensure it works for 95% of Android devices if you give me another three weeks and access to these 30 other devices (maybe on some website that offers paid access to them for a bit of time). Right now it works well for 75% of the devices. Now, the person who owns this business may consider his/her money better spent when you implement some other feature on both Ios and Android rather than ensure you support almost all of Android devices. It may not be the developer who chooses. Many times it may not be so clear cut too. It may be that some features get shot down during design because they are hard to get right on all the various aspect ratios and screen sizes that Android offers. So, yes the 'fragmentation' is a problem but in my experience it is mostly only to do with the variations in aspect ratio and screen size. Nevertheless, like one of the first replies to this topic (by bookwormAT) says, it is not as bad as having had to code for various Operating Systems if the manufacturers hadn't agreed to go with Android in the first place. So, Android does help us develop for a wide range of manufacturers' phones but it doesn't help much to ease the pain of accounting for the variation in displays.