why not but i'm afraid it won't dramatically change your productivity
I tried "Rescue Me", it's a good app to highlight how you spend your time in the day and then adjust your working hours. That's one of the main problems today with all distractions we get on internet. Use it 3 or 4 times and it's enough, I saw that way I waste too much time on social networks and reading articles (something I already knew but it's really impressive but when get real figures).
I tried several apps like this without huge improvements but I'll test "Plan", it looks cute and clear, may be it can help a little bit to adjust some small things.
Best tool that improved my productivity recently is Power BI by Microsoft, however it's not a smartphone app.