> It probably does nothing significant when the Play Services are not present Right, that's the part I care about. I think there are two possible situations:

> It probably does nothing significant when the Play Services are not present Right, that's the part I care about. I think there are two possible situations: - Signal's own open source code can detect the absence of Play Services and not call out to Google's proprietary code in the first place. Great, no problem there. - Google's proprietary code attempts to use Play Services and doesn't do anything when it's not present. In that case I do indeed trust Google enough that I wouldn't expect it to actually do anything else, i.e. the first option you mention.