Looking on the internet deeply has found these results:

applied to is the most popular phrase on the web.

applied in 178,700,000 results on the web	applied to 1294,000,000 results on the web More popular!
Some examples and use cases from the internet:	Some examples and use cases from the internet:
It is planned to introduce national independent regulatory authorities to ensure that the directive is applied in full. TSIs indicate the modules to be applied in the relevant Commission decision. applied in 2009. Diamond suspension or spray is applied in regular intervals during preparation. applied in 2003. CROATIA: candidate SERBIA: potential candidate Box 1 below summarises the penalties to be applied in connection with the infringements discovered.	It doesn't look like this phrase is very popular! The search could not find any examples on the internet.

applied in

178,700,000 results on the web

applied to

1294,000,000 results on the web

More popular!

It is planned to introduce national independent regulatory authorities to ensure that the directive is applied in full.
TSIs indicate the modules to be applied in the relevant Commission decision.
applied in 2009.
Diamond suspension or spray is applied in regular intervals during preparation.
applied in 2003.
CROATIA: candidate
SERBIA: potential candidate
Box 1 below summarises the penalties to be applied in connection with the infringements discovered.

It doesn't look like this phrase is very popular! The search could not find any examples on the internet.