Settings

Open Settings from the home screen. Here is what you will find.

Appearance

Theme: System, Light, or Dark.
Show tool previews: on by default. Shows brushes, shapes, selection modes, and fonts as picture cards / live previews so they are easy to recognize. Turn it off for a compact list if you prefer.
Brush sizes: a freeform Slider (any size), or four simple Preset sizes (S / M / L / XL). See Brushes.
Keep unsaved sheet input: on by default. If a sheet (like New Project) is closed by accident, what you had typed is restored when you reopen it.
Lock rotation: keep the app in its current orientation even when you turn the iPad, so the canvas does not reflow while you draw.

Set the frame rate and canvas size that new projects start with, so you do not have to change them every time.

Finger drawing: when off, only the Apple Pencil draws and your fingers are reserved for moving and zooming the canvas, so you never smudge a stroke with your palm.
Double-tap and squeeze actions for supported Apple Pencils (for example, switch to the eraser or the eyedropper).
Hover preview: shows a ring where the Pencil is about to draw, on iPads that support hover.
Tool outline: draws a ring showing the brush, eraser, or shape size at your fingertip or Pencil while you draw, so you can see its limits (the eraser's ring is dashed). On by default; you can choose whether it appears for finger, Pencil, or both.

Choose a backup folder and turn on Auto-backup to keep a safety copy of your whole library. See Your files, backup & restore.

See whether Pro is unlocked, upgrade, or restore a previous purchase. See DoodLoop Pro.

Send feedback / get support: opens the nubisco.io contact form so you can write to the people who make DoodLoop. Ideas, questions, or a complaint, they all land with us directly, and we can actually reply (unlike an App Store review).
Report a bug: opens the same form, ready for a bug report, with your app and device details already in the message so we can reproduce the problem. You write what went wrong there. No drawings or personal data are sent.
Open source: the open-source projects DoodLoop is built on, with their licences.
Version: the app version and build number (handy when reporting a bug).