If you don't have an Android 4.0 device, you could try using the Web version Keep on your device, but I wouldn't recommend it. Keep on the Web did not perform well in my tests using a Nexus 7 running Android 4.2.2. One-finger scrolling was very laggy, as was typing in a new note, making it almost unusable.
Anyone who uses Drive to keep all their content and isn't yet using an application for keeping miscellaneous notes may be very happy--or at least content--with Keep. If you are a dedicated note-taker, however, Keep's flaws will send you scuttling back to Evernote in short order.
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