The phrase "a flurry of apps" is correct and usable in written English.
It can be used to describe a sudden and rapid increase in the number of applications, often in the context of technology or software development.
Example: "In recent months, there has been a flurry of apps released that cater to remote work needs."
Alternatives: "a surge of apps" or "an influx of apps".
The restaurant industry has seen a flurry of similar apps.
"I'd love to report that this has generated a flurry of new apps.
The arrival of the newest iPhone has prompted a flurry of new apps, many optimized to make the most of its bigger screen.
Tracking your steps, calories, workouts and even your sleeping patterns became increasingly common, with a flurry of existing apps tied to external monitors, and some new ones (like Moves in this roundup) which simply used your smartphone's sensors.
As Roy Hodgson gears up to announce England's World Cup squad (or, at least, announce the bits of it that weren't already announced before the planned announcement) we're seeing the start of a flurry of football apps planning to capitalise on the tournament.
Expect this to lead to a flurry of AR apps, just like Apple is pushing with iOS 11.
In addition to Web sites, a flurry of mobile phone apps aim to make background checks as quick and easy as ordering a pizza: Just plug in a couple of facts like a name and birth date.
Among the more recent developments for insomniacs have been a flurry of mobile phone apps that claim to help lull us to sleep with specially designed combinations of nature sounds, white noise, hypnotherapy and music.
There has been a flurry of photo sharing apps released over the last year, with notables including Instagram, Picplz, and Path.
Ever since last fall, when Apple introduced its genial voice-controlled personal assistant, Siri, on the iPhone 4S, there's been a flurry of activity as other apps attempt to go beyond its limitations.
