Complaints of discrimination made by football fans to anti-racism group Kick It Out have risen by 269% in the past year, the organisation has revealed.
There were 284 complaints submitted to Kick It Out last season, compared with 77 the previous year.
The increase follows the launch of a mobile app with a reporting function in July 2013.
Racism (66%), faith-based abuse (20.5%) and homophobia (8%) were most commonly reported in 2013-14, Kick It Out said.
Of the faith-based abuse complaints, all but one were related to anti-semitism.
The majority of complaints submitted related to social media abuse (50%), then incidents attached to the professional game (26%), grassroots (22%) and professional players (2%).
A spokesman said: "Just over a year on, the app has made an immediate impact as it has become Kick It Out's most-used reporting mechanism relating to incidents within professional football - responsible for 38% of complaints registered with the organisation at this level of the game."
There were 142 incidents of football-related hate crime on social media reported to Kick It Out and passed on to police to investigate.
"One case led to a 21-year-old man from London being convicted and fined £150 having posted a derogatory remark on Kick It Out's official Facebook page in January 2014. A number of cases have seen individuals issued with cautions, and undertaking further education delivered by Kick It Out," the spokesman added.