Eventually all 3 major OS are having issues and customers are expect to get patches regularly.
Windows mobile was running great for ~10 years (2000 to 2010), most successful version looks like from 2003. Microsoft is working hard to regain their peak but struggling after 2010. iOS is running good for the past ~8 years (2007 – ), iPad version joined ~2010. Android is having a huge smartphone market share for the past ~6 years (2008 – ), Froyo was a good starting point from 2010 and tablets started using ICS from late 2011. Will revisit these 2 mobile OS status in 2018 holiday season.
Galaxies eating other galaxies.