Quick addition, and FREE
gpx.studio — the online GPX file editor
This little app (running from web-browser) allows for easy planning of routes and tracks. Once your plan is made, you can save your route as a .GPX file and load it into your favorite mobile app.
Looks simple but is actually quite powerful. Take into account that it does not save your tracks (no repository). It's just a small online tool. If you feel Gaia / Caltopo is a bit too complex, this tool could be ideal for you.
Next to the Mapbox Sattelite Imagery, you can also use Google Maps Terrain or Hybrid as layer.
Go to Settings, Layer Settings, Customs Layers. Make a new layer by adding these hyperlinks:
Google Hybrid:
https://mt1.google.com/vt/lyrs=y&x={x}&y={y}&z={z}
Google Terrain:
https://mt1.google.com/vt/lyrs=t&x={x}&y={y}&z={z}