This app was mentioned in 8 comments, with an average of 1.38 upvotes
I've been using Image Shrink for years, for resizing of images before email/upload (there's a free version too, which only seems to be limited to a single file at a time, pro version can do batch resize).
Too many things over-compress images, and sometimes you find yourself on an overpriced 3g connection, waiting 2 minutes to upload a 10MB image to have the far end resize/compress it for you when you could have just uploaded the smaller file yourself seems nonsensical.
Image Resizer app on the Play Store works a treat for me.
https://play.google.com/store/apps/details?id=com.gmail.anolivetree
Share the image to this app then it reshares the resized image to where you want it to go. A 'man in the middle' equivalent. Works great for my needs.
Hope it helps
Yes, that' right, not only very generic, but also very false, I rememberd the name incorrectly, the correct name is Image Shrink ( https://play.google.com/store/apps/details?id=com.gmail.anolivetree), sorry about that. There is also an unpaid version. Use this app for years on different devices, never wanted something different. Hope that's what you are looking for.
I've used Image Shrink for many years. It's super handy. Just share your photo (s) from the gallery or whatever app you are using to Image Shrink, it resizes them, then opens up the share menu again to pass the resized images on to whatever app you want.
Typical work flow: select half a dozen 18MP photos in Google Photos, share to Image Shrink which resizes them to 1800x1600, share menu opens up and I choose AquaMail and an email is created with all the resized images attached.
https://play.google.com/store/apps/details?id=com.gmail.anolivetree
Do they need to be full resolution? I use Image Shrink ( https://play.google.com/store/apps/details?id=com.gmail.anolivetree) to upload dozens of photos a day. A resolution like 1280x1024 in high quality comes in at about 400KB-500KB which means fitting a dozen on a single email is no worries.
As a bonus you can set it to strip EXIF data and rename the file, which is handy if you use the "filename based on location" feature of the camera but don't necessarily want that shared.
Try "Image Shrink":
https://play.google.com/store/apps/details?id=com.gmail.anolivetree
Best would be something like ImageShrink but for videos... https://play.google.com/store/apps/details?id=com.gmail.anolivetree