As per my experience with Taskbucks is that it is a malicious and Spyware app, while intallation of app it takes all permissions from you and when we start using this app we found that there is no such task which we have to complete rather that it suggest to install several other suspicious apps and give you some penny against installation and people dont rhink too much and just install such apps & compromise thier security.
After few time and mobile memory will full and mobile start misbehaving , but guess what your threshold for withdrawal is not a achieved and at last you feel cheated.
Beware of this app.