Call Recorder Smart has different recording methods. If you’re lucky enough, the app won't fail to record both sides over Standard API recording method without root. But you may need to check every audio source for Standard API in Settings > Recording > Standard API.
If you have tried every audio source for Standard API and the app didn’t record or recorded just your voice, it means that the manufacturer has either failed to implement, or blocked call recording on the system level.
Call Recorder Smart Features :
• Record phone calls
• In call control
• WAV, AMR, MP3
• After call actions dialog
• Search recordings
• Call confirm
• Edit info about recordings
• Volume control
• Dropbox and Google Drive support
• Manual encryption for WAV recordings
You need to have root permissions to try other recording methods. For root methods, it’s important to select correct device in Settings > Recording. Select a device with the same chipset if your device isn’t listed there.