Full Stack Developer needed to fix Bugs in our application DAB.

We launched an Android application named as DAB. It is a micro platform for artists to showcase their work. Right now we have launched its V1, and we need a V2 however, the product contains certain back end issues that needs to be solved such as crashing, slow back-end response and slow working on low end phones. We need a Full Stack Developer who can contribute 7-10 days full-time work in this project.