Learn German: Das neue Update gilt für alle Nutzer. - The new update applies to all users.

Gelten (to apply / to be valid) is a strong verb. Like many strong verbs with an 'e' in the stem, the 'e' changes to 'i' in the 'he/she/it' forms. Since das neue Update is a neuter 'it', the verb becomes gilt.

Why is it das neue Update and not das neues Update?

When you use a definite article like das (the), the article already does the heavy lifting of showing the noun's gender and case. This means the adjective only needs a weak ending. For nominative (subject) nouns, that weak ending is just -e.

Is gelten für a fixed phrase?

Yes! While gelten can be used on its own, gelten für is a very common fixed combination meaning 'to apply to' or 'to be valid for'. Whenever you use für, the noun or pronoun that follows it must always be in the accusative case.

What case is alle Nutzer in, and why?

It is in the accusative plural because it comes directly after the preposition für. Luckily, the accusative plural forms for alle (all) and Nutzer (users) look exactly the same as their nominative forms, so they don't change here!