He Samsung Galaxy J2 has a strong reception and good in-call audio. It comes with either one or two SIM card slots ( both are micro) , the Duos version has dual-standby. Only one card has access to 3G and 4G networks, the other is for 2G calls.
The call log is visible behind the keypad ( you can hide that to view the full list) and it shows which SIM was used to place/take the call. You can also filter the log by which SIM was used. The other two tabs show your favorite contacts and all you contacts