App to open pdf, customer sign with stylus, save and email document. need fast.

only proposals actually addressing my needs will be looked at!
i Have a joomla website, using sobi2 as a database. i have a button to open a file as a pdf on a phone or tablet (this button is tested and working)(those who know sobi2 will know the file as "details view") i need my customers to sign this pdf with a stylus or finger on a phone or tablet, enter some text from the phone or tablets keyboard, and then automatically send it to email adresses, previously entered in the app. so the app must have a interface to enter those email addresses (upto 5), and the ability to resize, and relocate the signature as soon as its entered. it also need a button to send (via email) and save, and a button to just save. this send function must regularly retry if it fails untill it is sent, or 48hrs pass. its main platform will be android, but must be convertable to apple. for reference an app with some similar functionality would be "sign my pad". on completion i will also be looking at getting an app made to simplify navigation of the site, so there is more work in it if im happy with the results. plz let me know how much you think this will cost, because i have no idea what it should cost. Thanks for your interest!