WAPTT

File extension waptt appears to be mainly related to WhatsApp, a proprietary, cross-platform, encrypted instant messaging client for smartphones now owned and developed by Facebook.

waptt files can be found in a PPT folder and appear to be audio, possibly from stored voice-mails received or made through the Push-to-Talk function.

The waptt suffix is appended to the actual file extension that determines the audio format of the file.

Example of the file may look like PTT-20160101-WAA0001.aac.wappt, in which the filename represents day (in this case 1.1. 2016) of the recording and the also the format of the audio (perhaps based on the settings in the app).

Sometimes, two files represent the same recording, each time in a different format. The second file type is usually saved in opus format, which is a highly compressed, lossy format designed for speech.

Note: It appears that in most cases the PPT folder (subfolder of WhatsApp) is not visible through standard file explorer and can only be seen with more specialized file manager or forensic tools.