This unlikely will not work as iOS and Android apps are not compatible with each other.
If you do not like the keyboard choices that came with the Nexus 7, you can download third-party apps such as SwiftKey, Swype, Emoji, and others.
You can get apps in the Google Play Store. Keep in mind though that not all apps are tablet-optimized. But, with over 700,000 apps out there, there should be plenty of choices.
There's currently no iTunes app for the Nexus 7, or for Android OS in general. However, there are various syncing apps where you can sync downloaded content from iTunes to any Android-powered device, which includes the Nexus 7.
You can either look at it thru the Play Store app (My Apps), or under Settings > Device > Apps.
From what i know the app store is a lot better than the kindle fire. The nexus 7 has around 800,00 apps compared to Amazon's 600,00 apps. Amazon has popular apps but not much important apps. Other than than that i don't really know anything else the nexus 7 can best the kindle fire at. The graphics and sound on the kindle fire HD is just AMAZING. So yea......hopes this helps!
You can get apps in Google Play store.
Office have not been released for android. You can use apps like GoogleDrive.
Safe mode is where your Nexus 7 is running with most of the apps disabled. This mode is useful when you are having issues with apps force closing or causing other issues and you want to diagnose what's going on. Instructions on how to reboot to safe mode are in the related links below.
The Google Play Store and the Amazon Appstore are two good places to find quality apps for your Nexus 5.
Nexus 7 accepts ePub and PDF format, but the built-in app doesn't allow you to load downloaded book into it. To read downloaded books on your Nexus 7, you need to install some third-party apps and a file manager app. See the related link for further information.
You can play music thru Google Music or the various streaming and music player apps available.