Recommended blocker software for android?

Hey there,

I often tried blocker software on my laptop in the past, but eventually got rid of them again after just a few days. I always said, that I must be strong enough to resist without a blocker in order to recover properly. But now - months later without much success - I want to install software to help me stay clean. For real this time.

I installed K9 Web Protection on my laptop, since I find it the best one out of all I tried. OpenDNS was too easy to work around. Until now, everything works quite well (only the forced safe search won't work, any ideas?).

I decided, that I want to have blocker software on my smartphone as well. Since I like K9, I searched for it on the Play Store, but didn't find an Android version. This brings us to my actual question: Do you have some blocker apps for Android devices you would recommend? I only want to block porn and nudity. It would be cool, if you could black- and whitelist specific websites and/or apps. Is there some kind of app, which can do that?

Thanks in advance for your help.