[Mobile] Improve model picker UX: quick reasoning control and persistent Favorites filter

[NANAMINER]

Problem

Changing models and model options on mobile currently requires too much navigation.

There are two related problems.

1. Reasoning effort is too deeply nested

If I only want to change the reasoning level — for example:

Low → Medium → High

I have to open the full model picker.

That picker is a large screen containing all providers and models, even though I am not trying to change the model at all.

Reasoning effort is something I may change frequently between tasks, so it should not require opening the entire model browser every time.

2. The Favorites filter does not stay enabled

The model picker has a Favorites filter, which is useful because I only regularly use a small subset of all available models.

However, if I enable Favorites-only, close the picker, and open it again later, the picker goes back to showing all providers/models.

This means I have to enable the Favorites filter again every time.

For someone with many providers and models configured, this makes the picker unnecessarily noisy and slow to use.

Proposed behavior

Quick reasoning control

Allow reasoning effort to be changed directly from the mobile composer/thread controls without opening the full model picker.

For example, next to the selected model:

GPT-… · High

Tapping High could immediately open a small menu:

• Low
• Medium
• High
• Extra High

The exact available options would depend on the selected model.

The full model picker should still be available when I actually want to change models.

Persistent Favorites filter

Remember the user's model-picker filter state.

If I select:

Favorites only

then the next time I open the model picker it should still show Favorites only.

Users who want the full list can disable the filter themselves.

An alternative would be a preference such as:

Default model picker view

• Favorites
• All models

Why this matters

On mobile, space is limited and model selection should optimize for frequently used actions.

I may have many models available through several providers, but normally only use a few of them.

The common workflow should therefore be:

1. See my favorite models.
2. Switch between them quickly.
3. Change reasoning effort quickly.

Instead, the current workflow repeatedly drops me into the entire provider/model catalog.

Related

• [Feature]: Remember reasoning level for each model #2324 — remember reasoning level for each model
• [Feature]: Support options in model favorites #3035 — support options in model favorites
• Favourite model section in the mobile app — previous mobile favorites discussion

Those requests are related but do not cover this mobile interaction problem: quick access to reasoning effort and persisting the Favorites-only view between picker openings.

Also related to Discussion #14038 regarding other missing desktop/mobile interaction parity.