The initial price and convenience of Google Photos/Google Drive (and similar) make it hard to resist when the images can easily move among mobile devices, desktops, and servers.  Our library creative staff use licensed Adobe tools to manage images through the publishing life cycle. SmugMug has a few users, too.

Every now and again on both Desktop and Web platforms ImageMagick helps transcode images between formats, resolutions, color spaces etc. - high resolution pictures, official logos, online catalog cover images. Some developers use irfanview, too.

If you care about privacy, then one of those paid photo management apps ought to work well enough. Read the usage terms fine print, check the app store reviews, and obtain a trial license.  Have a "sandbox" test/development mobile device and corresponding user accounts or testing- preferably a device that easily reverts to "fresh out of the box."