Identify the reading or comfort need
System mode links the app's light-or-dark presentation to the device. It is convenient when you already use a device schedule, but it can make the app look different at different times.
Adjust the relevant control
Choose System in Appearance, then inspect Fastly after the device changes mode. If a later change surprises you, check the system setting before assuming the app lost its preference.
Accessibility includes Reduce motion, Follow system, Larger timer numerals, High contrast ring, and Bold text. Fastly also follows device text size, so check both app and system settings for the effective result.
Check the real screen
The saved app choice can remain System while the visible palette alternates. The preference and its current visual result are different pieces of information.
| Check | Practical meaning |
|---|---|
| Appearance System | Light or dark from device |
| Accessibility Follow system | Motion and bold-text behavior |
Keep presentation and records distinct
Following system appearance does not automatically mean every accessibility preference follows the system. Fastly provides a separate Follow system option for motion and bold-text behavior.
Follow system concerns device motion and bold-text preferences. An explicit in-app reduction or bold-text choice can also request that behavior; review the combination instead of assuming one toggle tells the whole story.
A worked walkthrough
Consider a device that changes appearance automatically at a scheduled time. Fastly in System mode can follow that shift without another tap in Appearance. A screenshot captured before the change and one after can therefore have different palettes while both reflect the same saved preference. If you are investigating a preference that seems not to persist, check this relationship before troubleshooting storage. Accessibility's Follow system setting is separate: it concerns motion and bold text rather than selecting the light-or-dark palette. You can choose fixed Dark appearance and still honor device motion requests, or choose System appearance with explicit in-app accessibility choices. Reading these labels as controls with specific scopes prevents an overly broad interpretation of the word system. Verify each effective behavior in the actual screen where it matters, rather than expecting one switch to govern all presentation and device interaction.
Fastly is a lifestyle timer and journal. These notes explain the app and offer reflection prompts. They are not medical advice or a prescribed eating schedule.