No. Vivo S1 does not have auto call recording. But you can use Apps available on the Google Play Store.
No. Vivo S1 does not have any association with Dolby sound.
No. Vivo S1 does not have the FM radio support.
It takes about 2 hours time to fully charge Vivo S1 battery from 0% to 100%. Please note that Vivo S1 comes with a huge battery capacity of 4500 mAh. Hence despite fast charging support, it takes a little more time to fully charge the phone.