Softphone Dev for Android/iOS

I need a freelancer to white-label the Linphone open-source softphone into a branded mobile app for my service Unlimited World.

Requirements:

Replace branding: app name, logo, colors, and splash screen.

Deliver Android + iOS builds (ready for Play Store & App Store).

Integrate SIP login with our own PBX + GoIP gateways.

Each customer will be assigned their own SIM hosted in our GoIP.

SIP username = customer’s local phone number.

Support inbound & outbound calls through the customer’s own SIM (via GoIP).

Show call history (made, received, missed) inside the app.

Allow us to assign calls to agents (so agents can answer on behalf of customers) and show missed call alerts.

What We Expect:

Flat setup cost (no per-user/month fees).

Quick delivery — we need this live as soon as possible.

Freelancer must have prior experience customizing Linphone white-label.

Please confirm in your reply:

Your experience with Linphone or similar softphone white-labeling.

Estimated timeline to deliver both Android + iOS apps.

Your total cost for setup + publishing.

If you can also support us in future updates.

This app will be the front-end for our telecom service that combines voice minutes (via GoIP SIM hosting)