On what basis should I choose a drawing tablet and how do I know which kind is right for my use?

It depends on your needs and skills also .. but overall the best drawing tablets out there is Wacom.

For me the best drawing tablet is Wacom. 

1. In my opinion, it must be a Wacom tablet.
2. The most relevant technical specification is pressure sensitivity. The more, the better.
3. Smaller tablets are better, cheaper, easier to fit into your desktop, and they work just like the bigger ones. I would only choose the big model if you're going to use it for CAD.
4. Think about the use you'll give to your tablet. If you want if for painting, coloring and photo manipulation, it will be100% useful. For drawing, only Cintiq models are really good, and for designing, you need no more than a mouse.
5. There are second hand markets or brand new old models. They are really worth checking.

Well it depends on the range or genre of your skills all graphics tablet is good for digital art,3d and even photography for post processing and not all graphic tablets have good performance, so I recommend is Wacom Tablet, very useful, responsive, good tone of pressure and not so pricey as cintiq as their own higher level of graphics tablet which has a monitor. so if you have budget and your working performance need for advance level so cintiq is the best but as long you have a budget why not.. Cintiq is evey one's dreaming of because of its features and working performance so dynamic specially if you are working on animation, digital arts and industrial arts just like creating a design on luxury watches, jewelry etc.. so you have an Idea between the graphic tablet and cintiq..

Agree wth mr. Mahmud 

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