how many phone can bluetooth device linked concurrently

[qoboty]

Bluetooth device,use S110,can linked one phone,like example ble_app_uart, How many phone linked concurrently? Thank you!

[Stefan Birnir Sverrisson]

The S110 is a peripheral softdevice, which means the phone needs to be an central in order to communicate with it. A peripheral device can only maintain one connection at a time. If you let however nRF51 act as a central by using S120 softdevice, then you can maintain up to 8 links to 8 different peripherals concurrently, e.g. to 8 phones that act as peripherals. The S110 can however maintain a single connection and concurrently broadcast in non-connectable mode. Further ideas are on this thread

[qoboty]

If two Android phone act as central role, NRf51822 bluethooth is the peripheral device, which softdevice shall I choose S130,or something else ?