How do you hide text message alerts on an iPhone? rd.com, Getty Images (2) ... Examples of hidden messaging apps include Signal, Private Message Box, and CoverMe.

In the case of sending SMS messages, through simple programming, you can have texts go out automatically to selected contacts when certain parameters are fulfilled, for example if it's a ...

But a different feature entirely was added in a recent iOS update—‘Critical Messages’—that enables apps to send your iPhone highly important messages via SMS. Here’s how it works.

For example, it's possible to have iOS automatically remove any conversations that are older than 30 days, or any messages more than a year old. You can choose your preferred cut-off for old ...