(Update 2, 11-18-2013) I sold my Nexus 4 as I am getting my iPhone 5s. I still think Nexus 4 is a lot phone for the money ($199 before tax). Another feature I liked is the integration with google contacts, and google+ photo backup. I just found there’s an option on iPhone Google+ app for backup now.
(Update 09-16-2013) I agree with @PhillRyu that the back button on Android is nice, along with the multi-task button, it separate tasks from the home button (the iOS home button is a bit overloaded, it does both back and home, and double click home brings up the multitask thing).
(Original 09-08-2013) Last week I got my 1st Android phone, the Google Nexus 4. I bought it primarily due to its lowered price (from $299 to $199 before tax), and my 3 year old iPhone 4 battery is doing down hill (found a trick to save it after I bought the Nexus
I tweeted some minor problems/questions I have with Nexus 4/Android since then. Again for the most part, I am happy with the screen size, battery life (being new), and the sharpness of android in general. A few things I mentioned/complained in twitter:
1) Lack of a native Mail app, in iPhone I can add all the mailbox (yahoo mail, gmail) to the Mail app, in Android there is not a good very native app. But later I noticed the notification feature kinda compensated it. I did install the Yahoo Mail app. The Gmail comes by default.
2) Again on the email things, for some html formatted email, it appears iPhone can scale it properly the first time when the user opens it, on Android, it did not get right the first time. The workaround is move the mail left, then zoom (make it a bit smaller to fit in the screen). Not a big deal.
3) A bit sneaky: the Android recommend feature, in Youtube, Play store (music). Also the photo upload (to Google+).
4) Chrome web browser does not have a “reader” feature like Safari does: for better reading experience (filter out ads, and scale the web page).
5) Share it feature: initially I thought it only has the gmail, google+…after I installed the facebook and yahoo Mail, I found those are also available.