Hey there,
I'd like to ask you about the idiom 'TO SKIM/SCRATCH THE SURFACE'.
I know that it means 'to do, engage with or know sth only to a minimal degree, e.g. He doesn't know any foreign language well, he's SKIMMED THE SURFACE OF Polish, Spanish and French.

But can we use this idiom meaning 'to name a few'?, e.g.
- What's the problem with this app?
- Well, it's slow, full of bugs, keeps freezing and I'm only SKIMMING/SCRATCHING THE SURFACE.

Question

Hey there, 
I'd like to ask you about the idiom 'TO SKIM/SCRATCH THE SURFACE'.
I know that it means 'to do, engage with or know sth only to a minimal degree, e.g. He doesn't know any foreign language well, he's SKIMMED THE SURFACE OF  Polish, Spanish and French.

But can we use this idiom meaning 'to name a few'?, e.g. 
- What's the problem with this app?
- Well, it's slow, full of bugs, keeps freezing and I'm only SKIMMING/SCRATCHING THE SURFACE.

Answer

Yes you can. I am only scratching the surface can be used here. It means you are still figuring the app out. You have not yet mastered it.

Answer

Hello,
You do understand the meaning of the idiom, "to skim/scratch the surface". However, the phrase "to name a few" means giving only these as examples, even though more could be cited and it cannot be used in place of the idiom - to skim/scratch the surface.

I hope this answers your question. If you’d like to practice speaking. I’d be happy to help you develop a study plan. Feel free to view my teaching profile and class offerings and send me a message if you think I can help you. 
Regards

Answer

To name a few is not an idiom. Yes you can omit it or leave it in.
To name a few means= To provide only a few examples, though there are copious amounts from which to choose.