- Apr 1 1st automatic record changer introduced by His Master's Voice
- Apr 3 Interstate Commerce Comm transfers Ohio to Eastern time zone
World Record
Apr 5 Johnny Weissmuller sets world records in both the 100m and 200m free style swimming events
Historic Event
Apr 12 Kuomintang leader Chiang Kai-shek begins counter revolution in Shanghai
- Apr 15 Switzerland & USSR agree to diplomatic relations
- Apr 17 Japan's Wakarsoeki government falls, Baron Tanaka becomes premier
- Apr 18 Chiang Kai-shek forms anti-government in China
Boston Marathon
Apr 18 31st Boston Marathon won by Clarence DeMar in 2:40:22.2; his 5th victory in the event
- Apr 19 "Vagabond King" opens in London
Millions Come Up to See Mae West
Apr 19 Actress Mae West found guilty of “obscenity and corrupting the morals of youth” in a New York stage play entitled "Sex". She is sentenced to 10 days in prison and fined $500, the resulting publicity launches her Hollywood career.
- Apr 22 Roger Sessions' 1st Symphony in E premieres with Serge Koussevitzky conducting the Boston Symphony Orchestra
- Apr 25 Spain routes 20,000 soldiers to Morocco (uprising Rifkabylen)
- Apr 27 Carabineros de Chile (Chilean national police force and gendarmery) created
- Apr 29 Construction of Spirit of St Louis (the monoplane which Charles Lindburgh was to fly across the Atlantic) is completed
- Apr 30 Princess Juliana gets seat in Dutch Council of State