Looking on the internet deeply has found these results:

apply in is the most popular phrase on the web.

apply on 10 results on the web	apply in 130,100,000 results on the web More popular!
Some examples and use cases from the internet:	Some examples and use cases from the internet:
We recommend to apply on white background. Note: don't apply on shiny marbles. dried hair. Mix well and apply on towel Do not apply on damp wood or in rainy days. Application: apply on wet or dry hair. Don't apply on inflamed, injured or abraded skin. Soak a cotton ball into this mixture and apply on your acne.	This Regulation should apply in the transport sector. As a result, the latter may be inadmissible or impossible to apply in cross border situations. Such restrictions may apply in particular to participation in award procedures in the case of cross border cooperation actions. Article 5(2) of Regulation (EEC) No 2808/98 should apply in this case by analogy. This fundamental principle appears not to apply in Croatia. This figure does not apply in regenerative braking mode.

apply on

10 results on the web

apply in

130,100,000 results on the web

More popular!

This Regulation should apply in the transport sector.
As a result, the latter may be inadmissible or impossible to apply in cross
border situations.
Such restrictions may apply in particular to participation in award procedures in the case of cross
border cooperation actions.
Article 5(2) of Regulation (EEC) No 2808/98 should apply in this case by analogy.
This fundamental principle appears not to apply in Croatia.
This figure does not apply in regenerative braking mode.