Android app needed to fix now

Budget is 20$,it should not take more than an hour to 2 for experienced Android [login to view URL] do not apply if u r not expereinced ,its waste of your time and my [login to view URL] 5 years of exp is needed. Have an app code which you need to work on it. 1)Fix download button if app is closed. 2)There are 2 buttons a)Download b)Play Need to toggle to "play" button once download is completed. 3)If app is closed between download of file, it can restart to download from first again,if reopned the app 4)Currently if app is closed between downloading the file,it shows play button but it should not show "Play " button till its completely downloaded.