i'll say i suppose only thse security related app are likely to be trustable, like the 2FA, pin lock etc.
for other apps i'll treat them as plain text stored.
i'll say one can use "pattern launcher", and when pair with backward helpers, use the one that swipe back to the clock, NOT the launcher.
The pattern launcher already is like a screen lock, except that a press of button or a 10s press of button will boot into launcher or reboot, in both ways you are defeated.
thus next level is:
disable the physical button as in the manual. ;
downside is if your watch halt, you cant immeditely reboot. (if just slow, i wrote a soft reboot app but not yet put in the bangle store).
but as bangle's SWD is exposed, i guess we will never brick one, is it?
ps: it's like android in version 2. only screen lock and no encryption.
we better have to wait till bangle 3 or 4 in which the encryption is built in -- the cpu/ram/rom is not prepared.