Climbing near the peak of the rankings of late is one service that doesn't fit that mold at all.
Remind, which provides a free secure app for school teachers to communicate with students and parents, soared as high as No. 11 this week on the iPhone as the new school year kicked into gear.
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Not that co-founder and CEO Brett Kopf is surprised. His company has 25 million users, including about 35 percent of primary and secondary school teachers. Last year, the app peaked at No. 3 in the Apple store on Aug. 24, adding 315,000 users per day.
As the 2015-16 school year gets going, Kopf is planning for days with up to 400,000 sign-ups.