Please respond if you have used either Instapaper or ReadItLater with your thoughts on your app, which you tried, surprises of using the app, what you like and what you dont!
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I have been using Instapaper for a little while now. I really like it, is it such a useful tool for marking pages as "to read" so I can get back to them at a later time. Even better that it's web-based, and so can be accessed anywhere. I haven't had any problems or surprises with it yet, and am enjoying the utility it offers.
I've been using instapaper for quite some time now. Instapaper makes more sense if you're an iPhone user, lots of iPhone apps seem to have better integration with instapaper.
I use instapaper heavily when I'm on the go and see links on twitter - with Osfoora ( my twitter client on iPhone) - I tap on the link and add it to instapaper.
I also like that instapaper has got support for folders, so you can group related articles. And you can also email the link to be added to instapaper.