Need Full Stack Developer To Develop Mobile App For Tally/Busy

Hi I am looking a full stack developer to develop an accounting software. Mobile App for Tally/Busy 1. Get Tally/Busy Data on Cloud and Accessible on Mobile 2. Time to time synk/update data from tally/Busy to mobile app. 3. On mobile app user can display any report and send it to any one by mail, sms link, whatsapp. 4. Focus on Basic details of outstanding and their follow-ups details just like basic CRM 5. we can enable entery lable access Via mobile app and entry should appear in their Tally/Busy Software. (Two way synk) Get Tally/Busy Data on Cloud and Accessible on Mobile a) User visits website or Google play store, downloads and installs a app b) This app connects with TALLY/Busy (Backend process) at the time of installation and ask simple configuration (i.e Tally/Busy Serial Number) and gets user Tally/Busy data of open company/s in suitable format and uploads this data on webserver in suitable database format [mysql/postgresql etc which ever you comfort]. c) In configuration remember some points like Tally/Busy is Single user or Multi user, Number of user in same software, number of companies in same serial number and user creation and security. d) Our software running on server that connects with frontend [android/iOS] and Backend queries data and sends info to user as required from API. Execution Logic i. Our mobile app should runs in autoexec on startup each time, and syncs data with TALLY/Busy and uploads on server on fixed intervals. ii. Our app should check for TALLY/Busy connectivity each time it wants to sync and raise an error/warning in case either connectivity is missing. iii. For syncing, logics need to be developed so that after first upload all data one time and next time only changed data in TALLY/Busy should be uploaded. Changed data mean : New vouchers, Altered Vouchers, Deleted Vouchers. (use can use each transection ids. Remark for deleted voucher: Deleted Voucher ids are not available in tally/busy. One option is to upload all data each time TALLY syncs, but this is not rightway and will take huge bandwidths when we scaling up. So we store all Voucher id in uploaded server database by syncing, we compare voucher id from uploaded database as well as tally/busy database. If id exists in server database but not in tally/busy database, we assume that voucher has been deleted in tally and we remove from server database. This will require ids in both databases to be compared each time sync happens and then data interchange happens on basis of results . [example “id” in tally/busy but not in server = new data, alter “id” in tally/busy= altered data, “id” in server but not in tally/busy = deleted entry