Ridership on the MBTA rose for the 15th consecutive month. The transit agency announced Wednesday that it had a weekday average of 1.371 million passenger trips in April, a 4.4 percent increase compared with the same month in 2011. The jump was fueled largely by bus ridership, which topped 400,000 for the average weekday in consecutive months for the first time. Acting MBTA General Manager Jonathan Davis credited the boost in bus ridership to real-time data available via smartphone apps. He said more than 100,000 smartphone users have downloaded apps that provide arrival time information for more than 180 routes. Davis also credited the economic recovery and improved employment numbers. The Massachusetts Bay Transportation Authority also had a 12 percent increase in commuter boat ridership.