Hopefully the advice also will help other readers. I'm not sure why the original iPad has slowed with iOS 5. Could be deliberate by Apple to force us to buy new iPads or something technical, like the processor can't handle the demands of the new OS. Only Apple can say for sure. The same could be said for carriers not upgrading phones to the latest Android release, or manufacturers releasing new phones with older OSes and a promise for future updates. Only the carriers, Google and their partners know for sure.
In real terms, iOS's 365 million devices to Google's approx 300 million Android devices, this gives IOS the lead in overall market share and 73% of mobile profits to boot. The App Store has over 600K apps with over 200K of those for iPads. Again, this gives iOS the lead over Google Play's 500K apps and about 1000 apps for their tablets. To date, the App Store has generated over $13 billion in revenues and paid Devs $4 Billion. Compared to Google Play, which has generated $1.1 Billion and paid Devs $320 Million, it's clear the App store is much more profitable. Devs favor iOS in general and they make 10 times more money. This translates to more and better apps for iOS users like you and I. Google Play was predicted to overtake the App store last year! That didn't happen and doesnt seem likely.
Third party app stores are a security risk for Android and have been responsible for several malware outbreaks. This is in addition to Google's own Google Play store. While no approach is totally secure, the risks are reduced considerably under Apple's curated eco system, the Apps are better and OS upgrades more streamlined.
To me Android is uninspired and lack the beauty and simplicity that makes me prefer iOS. I've been involved in tech for many years, and that experience tells me IOS is the better choice. I'll deal with its issues, as I have for years, but Android isn't an option I'd give a second thought.