Application development initially for Android

General information for the business: This is to be a music sharing & recording application for consumers ranging from 10 upwards....
Kind of development: New program from scratch
Description of requirements/functionality: We are looking at developing a music application for android and want to create a cut-down pilot version of the application to test the water. Essentially the application will initially only be developed on Android and will allow registered users to download a beat (lasting no more than 30 seconds) of their choice which we will create & provide. Initially there will be 6 beats to choose from. Once downloaded the user can then record their rap/spit with the beat and then upload it for other users to listen to it, share it etc... &, also for other users to score it out of 10/give it stars etc..... There will be 6 classes/groups of users grouped by their age i.e. 10 - 13 years of age; 13 - 15; 16 - 18; 18 - 21; 21+. Like street rapping competitions but all done on line. This is the essence of it...key is to keep it as simple & user friendly as possible so any advice &/or suggestions would be welcome.
Please can you advise a cost & timescale asap. Looking at having a pilot app ready for testing & playing with by end of this month/beginning of Jan 2015. Look forward to hearing back from you asap. Yours sincerely, Jon Ambrose
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