The free options are genuinely good. Adobe Scan turns pages into clean PDFs with automatic edge detection and text recognition, free. Microsoft Lens does the same and drops files straight into OneDrive. Google Drive's built-in scan on Android is the zero-install option. iPhone owners get a capable scanner inside Apple Notes. For most application documents, these cover everything.
So what does paid buy you? Usually three things. Batch scanning without watermarks. Better text recognition for long documents. Cloud extras like editable text export. Some free tiers stamp watermarks on your scans, which looks sloppy on a transcript upload. If a free tier watermarks your scans, that alone justifies switching. Free or paid, pick the one that does not brand your documents.
My take: start free, and only pay if you hit a real limit. Scan one transcript with Adobe Scan or Microsoft Lens. Zoom in. If every line is readable and the file is under the portal's size cap, you are done spending money on this problem.
The habit matters more than the tool. Scan everything the week you receive it. Name files clearly. Keep a mobile app to track application documents so you know what is scanned, uploaded, and confirmed per school.
Know what you are scanning toward. The application document requirements database at applicationreview.fyi lists documents required for university application abroad by program. When the packet is complete, get your application audited before you submit.