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I completely agree that the ESP32 Bluetooth consumes a lot of power. I noted above that it seemed to require 40ma even if not active and so I removed it completely. This post https://github.com/espressif/esp-idf/issues/947#issuecomment-500312453 would seem to indicate that Bluetooth on current ESP32 hardware is a lost cause as you need an external 32.768Khz crystal to get effective low-power performance (yes, it uses 1 second advertising!).
Overall, I think the T-watch is great as it has a large bright touchscreen but it would be of much more practical use as a smartwatch if it was based on low-power Bluetooth SoC such as an NRF52840. (I have a P8 - NRF52832 - on order! )
jeffmer-
I have a P8 - NRF52832 - on order!
Great watch for the price. This weekend I got SPI flash storage working together with the display (it has shared SPI pins between spi flash and display so was a bit tricky) so code runs from SPI like on Bangle, @enaon does great things with P8 and is always out of space so he nudged me to get it working.
fanoush
Also turning on Bluetooth Low Energy drains the battery fairly quickly. However one guy managed more than one day with BLE 'on' by runing BLE advertising every second (yes 1 packet sent each second) Then the horrible power drain with BLE turned on averaged into something reasonable.