Anything SAP has in it' "quiver" for UI's are/can be used for infotype operations.
- SAP transactions (dynrpos) via the SAP GUI (example, PA30)
- ITS (yep, old old old ESS still lives! haha)
- BSP
- WebDynrpo JAVA
- WebDynrpo ABAP
- WebDynrpo ABAP - FPM
- Adobe Interactive Forms
- SAPUI5 / FIORI apps
...and that's just off the top of my head and not including any other "custom" application/interface that 3rd parties or customers can do themselves as well (example, .NET applications using "connectors" or pure JAVA apps using "connector" for JAVA).
What is it you are actually trying/wanting to do and that will narrow it?