While cotton bud swabs (aka Q-tips) are commonly used for electronics cleaning, they can be blunt instruments for dense PCB designs. Techspray offers a pointed cotton swab (part #2313-30PK), a pointed foam swab (2309-1000) and small rounded foam swab (2311-1000) for cleaning tight areas.
Yes, cotton swabs are a common choice for electronics cleaning, cotton tends to lead behind threads and particulates. Open cell polyurethane foam swabs are a common, very clean replacement for cotton.
Just about any swab is compatible with isopropyl alcohol (IPA), but harsh solvents like acetone or toluene can cause foam swabs to swell and even break-down. For harsh solvents, cotton swabs are the best choice.