Reading settings that preserve your place

Choose between named sizes and fine adjustment deliberately

Galatea groups font size, line spacing and brightness in an Appearance sheet, with three named font styles above them. Dipsea offers four named text sizes and a small set of color choices. One provides finer adjustment, while the other reduces the number of decisions needed to find a readable page.

Named sizes are easy to select but need a clear current state and a meaningful difference between options. A slider permits finer tuning but should announce its value and support adjustment without a precise drag. Do not treat a small A and large A as sufficient accessible names. Explain that they change reading text rather than the surrounding interface.

Preview the actual passage, not a decorative alphabet sample alone. Real paragraphs expose line length, punctuation and paragraph spacing. Leave enough text visible around the sheet to evaluate the change, or provide a preview area within it. If controls cover nearly everything, the person has to alternate between editing and guessing rather than adjusting and seeing.

Explain spacing as a layout choice, not another font size

Storytel separates font family, line height and justification, with a visible 125% line-height value. Litres presents numeric text size, line spacing and side margins together. These controls affect different aspects of the page even though all can change the number of visible lines.

Keep one label per variable. Larger text changes glyph size; line spacing changes the distance between lines; margins change the width of the reading column. Increasing all three at once through one vague Comfort slider makes the result hard to understand or reverse. If a theme bundles them, provide a way to inspect or reset the bundle.

Use units only when they help the reader predict an effect. A numeric size needs a consistent scale, while a percentage needs an understandable baseline. A font choice can also alter line breaks at the same nominal size. Test long words, punctuation and paragraphs with links so the controls remain useful beyond the short sample used in a design mockup.

Distinguish the page theme from the whole app

Wattpad includes Follow Wattpad app settings beside page-color choices. Ascension separates Viewing options, Reader Options and Audio Options, with Theme set to System. Both make a relationship between reading preferences and wider defaults visible, rather than presenting every choice as a permanent global override.

Define a simple preference hierarchy: system or app default, an explicit reading override, and any book-specific exception you actually need. Do not add all possible scopes by default. The reader should be able to tell whether a choice follows future system changes or remains fixed. A dark page and a system-following theme can look identical now but behave differently later.

Keep audio settings independent from text unless the person explicitly changes both. A shared settings surface can be convenient, but adjusting line spacing should not reset playback speed or autoplay. Preserve the current audio position while the text reflows. The interface should let people customize one mode without having to rebuild the other.

Treat reflow as a position-preservation problem

Dreame places font size and spacing beside Scroll, Flip and Slide choices. Leap Ahead shows numeric size and line spacing next to font families. Those settings can change both the shape of the text and how the user moves through it, so their implementation needs more than a remembered scroll offset.

Anchor the reading position to stable content, such as a paragraph identifier and an offset within it. A pixel position or page number may become meaningless after a font change. Restore the relevant passage after reflow, allowing for the newly visible number of lines. Do not jump to the beginning merely because pagination has been recalculated.

Separate changing page movement from enabling automatic scrolling. If auto-scroll is supported, make its active state and stop action clear. A person exploring appearance should not accidentally start moving text. Test a font change near the end of a chapter and a change from scrolling to pages, where a small restoration error can skip the remaining passage.

Make reset and font availability honest

GrowMe places Reset in its Themes and Setting panel. MoboReader shows a Font Settings surface with Default font as the available selected option, while the broader settings remain behind it. These examples raise two useful questions: what reset restores, and what happens when the current font choices are limited.

Name the scope of reset. Reset theme should not erase bookmarks, notes or reading progress. If reset also follows the system again, show that resulting state. Keep a safe default available when a custom font cannot load. Do not leave blank text or silently substitute a different layout while still labeling the selected font as active.

Avoid promising a reading benefit based on a font name. A specialized typeface is an option to evaluate, not evidence of a clinical or comprehension outcome. Let people choose what suits their own reading and provide a reliable route back. A small set of functioning preferences is more useful than an extensive menu whose fonts are unavailable offline.

Store content position separately from appearance

Keep a reading anchor, preference values and their scope as separate state. Apply a layout change, wait for the text to settle, then restore the anchor. If the book format has fixed pages rather than reflowable text, explain the different controls available instead of offering a font slider that cannot affect the document.

Retain preferences across navigation according to the stated scope, and reconcile them when fonts or content are unavailable. A cancelled settings surface should follow one explicit rule: retain immediate adjustments or restore the previous snapshot. Do not let the visible close button and gesture dismissal disagree. Preserve annotations through either route.

Test controls with large system text, screen-reader input and long translated labels. Keep the selected value distinguishable without color alone. Changes in the reader should not make the settings themselves unreadable. For a continuously adjustable control, avoid announcing every redraw as a new page; announce a useful final value and retain a predictable focus position.

Ask the reader to find the same sentence again

Have a tester locate a passage, enlarge its text, change the page theme and return to reading. Ask whether they can find the same sentence without searching. Repeat near a chapter boundary, with an existing highlight and with a missing downloaded font. This tests the actual purpose of customization rather than the visual appeal of the settings sheet.

Track failed preference saves, unexpected resets and position-restoration errors. Frequent changes do not automatically indicate a bad default; people may read in different conditions. Examine repeated corrections at the beginning of every session, which can reveal an override that is not persisting where the user expects.

Check that the controls remain usable offline and after the app restarts. Compare the restored passage, not only the stored numeric font size. Avoid collecting the reader’s private passage text merely to measure a setting change. The product can validate state transitions and restoration without turning reading content into unnecessary analytics.

Review the complete customization task

Use these checks on a working build, not only on the polished reference state.

• ✓Can the reader judge changes against a real passage?
• ✓Are size, line spacing, margins and font distinct controls?
• ✓Is following the system different from an explicit page override?
• ✓Does reflow preserve the current passage and annotations?
• ✓Do scrolling, pagination and automatic scrolling remain separate choices?
• ✓Does reset restore preferences without erasing reading work?
• ✓Are missing fonts, offline use and accessible adjustment recoverable?

Connect reader controls to the surrounding system

The mobile color and typography review covers the wider visual system. Reader customization adds user-controlled values and persistence to that foundation.

Compare Bible app design examples when reading, audio and study actions share one product. Keep appearance changes from disturbing those other tasks.

For a current first-party reference, Apple’s Books reading guide documents separate text, theme and layout adjustments. It describes Books, not a universal requirement for every reader.