Secure texts and data reception

As an increasing number of countries and quite clearly providers are storing our calls and messages, possibly even looking and listening during calls or texts, it looks like keeping ahead of the game is the name of the game. Internet via smartphones is highly susceptible. That also includes hacking which, for instance, might give those who are not the state therefore doing so in the name of 'security' gaining access to our bank accounts by use of back doors.

I am thinking about eventually using a downloadable software on my phone. Threema seems to cope with even slow and difficult connections and is something like €1.99 a month to subscribe to. Signal is a free open source software (Edward Snowden has apparently recommended it). I have looked at both, imagine there are others, but wonder just how long they are secure and how often we need to upgrade or change software. I often receive sensitive information, indeed at present seem to have a lot, but at the same time I have lived with the fact that what that is is never sensitive in a way that affects national security or anything like that so perhaps I should simply accept the possibility of snooping and that data being passed on to those who might be interested, if they haven't already got hold of it.

I am not paranoid about these matters but more concerned with preserving my privacy, as I am sure many other people are. What do you people think about these issues and are any of you using software to keep your data reception secure?

Threema works at 1.99 € one time fee.

Telegram apparently is also one of the most secure encrypted text messaging app and Free of charge.

I have used both and am sticking to Telegram currently.

Some of my contacts are still on whatsapp, skype so there is no way for me to have full control of my privacy.

Have you watched the movie - great detail on how our lives are being monitored.

I'm also considering a VPN for 4-5 devices. Knowing that everything I do, buy, say, (mean?) is being tracked and stored somewhere (metadata) is frankly quite frightening.