Your app holds four different models. There's a menu where you pick, and most people never open it.
Tap the model name at the top of the app. Four options appear, and each one is built for a different kind of work. Picking the right one is most of the skill.
On Max, the most capable everyday model is already your default. On Pro you open the menu and choose. On the free plan you get fewer options, and that's fine for a lot of what follows.
The fastest. Use it for a quick answer, a date, a spelling, a conversion. Speed matters more than depth here, and it's the right tool for anything you'd otherwise google.
Most efficient for everyday tasks, and your sensible default for a normal week. Drafting a message, tidying a list, answering a straight question. It's quick without being thin.
Built for complex tasks, and it checks its own work as it goes, so you correct it less. Reach for it when the answer actually matters. Planning the week around three sets of commitments. Turning a pile of school emails into one list with the dates pulled out.
The top of the range, for genuinely hard problems. Included on Max plans, or available with usage credits on Pro.
Using the most powerful model for a spelling check is like taking the Porsche to the corner shop. It'll get there. It just isn't what it's for.
Open the menu, see which one you're on, and pick on purpose.