HI. Wanleytron.
I just checked your project document and write this message to you.
Regarding your project, I've good experience about Signal Processing more than 5 years including speech recognition,etc.
And I've good experience about Android application, especially I made several Android Apps Like As ( MMGuardian, ScreenVision, skipmp3, MonitorApp, etc) and I 've majored in development fields more than 8 years.
So I just bid your project and thanks to this opportunity.
As you can see, I am newbie on freelancer, but I am so proud of my skills and experience and I will be senior freelancer ASAP.
Well , If you hire me, then it's my first task on this freelancer, and I will complete it and give good feedback from you.
According your project , doorbell means alarm, doesn't it?
Well, I will wait your reply here.
In addition to we have to discuss about price and duration .
Thanks for your project and thanks to reading my message.
I wish I could have good luck for do your project.
Regard.
DevFiend