I have been trying to find the best way to reduce image sizes and add text to images in Android phone and Chromebook.
I choose 320 or 640 pixels wide for Thumbnails on my websites, and 1600 pixels wide for Zoom presentations.
Chromebook double click photo in Files app to edit: crop (with presets) & resize, but not add text. Alt+select file to open in Resizer or Snapseed.
Photo & Picture Resizer (free version) works well on my phone and Chromebook, at the cost of a few ads. You can select dimensions as percentages or preset sizes, both with Custom options. You can also Rotate and Crop (preset & free). Saves a copy in Pictures | PhotoResizer folder by default, but can replace the original (with suitable warning).
I can add text in Photos or Gallery on my phone, but apparently not on Chromebook. Then Upload to Photos (ccpcgc) and add to Thumbnails album.
I tried Phonto on both, but it seems to make much bigger files, some of which are slow to display on websites, so I uninstalled it.
Pixlar is well recommended, but over-cluttered, so I have uninstalled it. It can open images in Google Drive,
Polarr is also recommended, and I could use it to add text on Chromebook.
Polish Photo Editor can crop, adjust, fit, add text and more on phone, including collages. Interface hardly usable Chromebook.
Snapseed has a vast range of features, but I cannot see how to resize images. Wide choice of text styles. You can choose Snapseed in More Actions in Files app.