This is an excellent app!!! I use it myself and was just about to recommend it. Very easy, very useful!!
for those of you concerned about signing up, there are no costs involved for the free version .(I purchased pro from the playstore and payed R59 ZAR for it, thats like 4 dollars.. and its totally worth it!
be warned tho, the GUI (display) is loaded onto the arduino as part of the source code, this makes it very handy because you can connect from any android device and receive the display screen without having to download the new GUI to the phone, but if you are an idiot like me and not aware of this you will search for a way to download this or send it to your android device separately which is not possible.
Excellent app!!! use it!! super easy!!! great explanations and examples!!