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Google drive
Google plus for photos

icloud for music and videos purchased from iTunes

Google play music

If you're in the UK:
BLINKBOX
Sky Go
 
GoodReader is a good app too - it connects to most cloud services, plus to other network drives. It's a doc viewer (supports several formats), but also great for managing files. I'm not describing how great it is, I suggest you look at their site to understand all it can do, it's one of those apps that I think might have started as one thing, but continued to grow with features and now does so much. Their page is here.

Dropbox is for me the most valuable app, already listed, and if you do all the right things you can get 6GB for free - this site explains it here. Actually you can get up to 16GB, but 6GB you can get by yourself, and since you've got limited storage on your iPad, free cloud storage is invaluable. SugarSync used to be good, but now they charge. Spider Oak is good - you can get 2GB free from them, I use them also you may want to check them out (they're particularly good at privacy).

Evernote - I love this app, can't say enough good about it. Plus, if you want to use your iPad for recipes storage, the sister app Evernote Food is great too. Both are free (though you can subscribe to advanced features in Evernote).

Of course reading apps like Kindle and iBooks, especially Kindle as you can view the books you store in the cloud, download a book, read it, delete it and it'll still be in the cloud.

Hope that helps, 16GB is not a lot of storage, but with some of these apps it is absolutely manageable (and not difficult).
 
Box is a cloud storage app that offered 50gb of storage free when the first ipad mini was released, if you downloaded their free app.
I did download the app and use it along with Evernote.
I have all of my photo's and many, many songs and albums on the site, along with 30 or more movies and haven't made a dent in my 50gb account.
they still give a reasonable amount of storage to ios users just for signing up.
Box has been very reliable and they have many useful features.
 
All these sorts of threads really repeat the same apps… you could just do a search and will come up with many. Wish there was a thread with unique suggestions. For example: my most used apps on my iPad are (other than those mentioned): 2Do, Matcha, and Notes Plus.
 
Good suggestions guys, thanks

It does bring up a question I had... If you upgrade to premium Evernote for offline access, does it download everything and suck up a lot of memory?
 
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