Google's Play Books & Cho Chikun’s Encyclopedia of Life and Death

[Kungfu_Panda]

Vit Brunner created nice PDF versions of various tsumego (go problems) collections; download them for free at:

Tsumego Collections

If you have an android phone, you could upload these PDF’s to google’s play books

By using the bookmark function (single click on the upper right of the page) you can keep track until which page you solved them all

I like this app because swiping to the next page look great

You won’t find solutions in Vit Brunner’s collection, but the problems are nice.

[Odo]

I have had these on my hard drive for a while. They are excellent.

[Françisa]

I printed them and work on them at my coffee table.

Wish I heard of this solution before printing them, hehe.