how to read someones text messages?

The honest answer depends entirely on whose phone it is, so let me split it three ways because the rules are different for each.

Your own device, or a child's device you administer. Full access is lawful and, on Android, straightforward: SMS and messaging are readable by an app with the right permissions. On iPhone, Messages is end-to-end encrypted and Apple exposes no content API, so the only route is the child's iCloud backup with their account — restore it to a spare device to read. Ultimate Phone Spy handles the Android side, plus Windows and Mac, from one dashboard (sms tracker, system requirements).

A partner's or another adult's phone. In the US, reading someone's messages without consent can violate the Wiretap Act and state privacy statutes even on a shared family plan; in the UK and EU the equivalents are the Computer Misuse Act and GDPR. Two consequences people underestimate: the evidence is often inadmissible in the divorce case it was gathered for, and the act itself can be the counterclaim. If infidelity is the concern, the paths that hold up are shared transparency agreements, a forensic examiner working under legal instruction, or a licensed investigator.

Someone else entirely. No.

On the technical side, ignore anything promising remote SMS reading from a phone number. SMS is not stored anywhere a website can query; "read texts from any number" tools are credential phishing. The realistic options are always: physical access to the device, the account backup, or the carrier's own records with a legal order.

If you are parenting, the durable setup is transparency plus limits rather than a secret feed — the child knowing the boundary exists is what makes it stick.