The oyster app offers a simple User Interface and superb audio quality VoIP calls at affordable rates. Oyster works on all iOS devices and supports calling over WIFI/EDGE/3G/LTE. In order to use this, app end-user can register with their mobile number.
Key features include:
1. Lowest battery usage with highest reliability/stability on the app store
2. Lowest latency of all iOS softphones.
3. Exceptional voice quality.
4. Bandwidth normalization.
5. Voice/Video packet negotiation
6. Bluetooth support.
7. Excellent audio quality
8. Supports calling over WIFI/EDGE/3G/LTE.
9. Background/multitasking support.
10. Integration with the native iPhone contact list.
11. Speakerphone mute and hold.