As an AI language model, I don’t have real-time data. Moreover, the popularity of betting apps can vary depending on location, specific sports events, and personal preferences. However, here are some of the popular and well-known betting apps:
1. Bet365
2. William Hill
3. Paddy Power
4. Ladbrokes
5. Betfair
6. Unibet
7. 888sport
8. Betway
9. BetVictor
10. Coral
Please note that this list may not represent the most downloaded betting apps this year, as the popularity can vary. Additionally, it is always recommended to check the relevant app stores or online sources for the most up-to-date and region-specific information.