Some sort of android tablet then you could add a bluetooth keyboard/case down the line to turn it into a laptop style device. You could also look at a chromebook in that budget.
A Tablet would allow you to take advantage of portability, use in car, use GPS in car, bed, sofa, etc... Chromebook is more of a desktop style laptop. Both are equally capable, just different. A Tablet with Android is more common, and Android is more common with millions of apps available. A Chromebook runs chrome so it's not android. Some Chromebooks can however use android apps from the google store.