So if you're worried about your phone being snooped at the border, mainboards are very reasonably priced in Chinese websites for many Android phones. Put in a

So if you're worried about your phone being snooped at the border, mainboards are very reasonably priced in Chinese websites for many Android phones. Put in a new mainboard and there won't be anything compromising on it. If customs takes it out of sight, throw away the mainboard or send it to a security researcher.