After my time with both platform and constantly scanning google play, i will say that as long as phones are concerned, apps in most categories are pretty good now. Many iOS apps have counter parts in android which sometimes also give more functionality due to the OS flexibility.
On the tablets, it is improving. Some real good android phone apps have tablet versions which actually look like they were made for a 7 or 10 inch screen (or for sizes in between), so we are almost there.
There is one lacking aspect though, games. Now if you are a Gameloft, EA, Rovio games fan, or those simple temple run and plants vs zombies type-ish games that everyone likes because they are *too* casual (seriously, they barely need any processing effort from the brain), you will be at home. But many indie devs publish great games on iOS which have taken more of my play time vs. AAA titles (which lack depth being the fact they are mobile games). Examples are kingdom rush (with the sequel in tow), battleheart (android version is behind in updates, and mikamobile has stopped their development for android), pixel people etc. Heck even street fighter mobile is off limits. I frankly don't know why developers are still hesitant to make these available on android now that the hardware is top notch, the software has matured a lot, and the marketshare is impressive.
Even EA sometimes refrains to publish all titles as well.
Then there are the apps put by your local businesses, services etc which sometimes are not produced for android.
This is not a big deal for android enthusiasts may be, but having all this available on android phones and tablets would be great, and i am sure everyone would love it too!
My platform of choice would definitely be android if i could run all my iOS apps on one. It is the apps which have me tethered to the iOS world. Considering it is the other way around when it comes to mac vs. PC, i am completely surprised that iOS still enjoys quality app selection edge over many platforms despite its bigger brother OSX failing in that for years.
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I love how the Play store shows you how many downloads each app has
I agree with the rest of the comment, but the above makes little sense. I have seen amazing apps which barely get noticed and have 100-500 installs, and some useless stuff which i am not interested in that has millions. Downloads means little for app quality IMO.