David Lieb, founder and CEO of iPhone app Bump yesterday posted some data on Quora to a question about what percentage of users of iOS devices were on 4.x, his answer revealed that 89.7% of Bump users were on the latest major iteration of iOS, 4.x.

Although Lieb didn’t note how big the sample size is, the latest known figure of Bump downloads was 15 million back from August last year. That’s a large sample size and one that includes users of iPhones, iPod Touch’s and iPads, a sample that would suggest the ~90% is a close approximation to the real percentage of iOS device users on the latest major iteration of iOS, version 4.

Ian Peters-Campbell of Loopt, another iOS app backed up Lieb’s data but said for his users take-up was even a little higher. Anyway you cut it such a high take up rate in about six months is impressive. It also highlights concerns over how fragmented Android is compared to iOS which back in December 2010 when Froyo (2.2) was the latest Android OS only had 43.4% take up, let alone Gingerbread (2.3) which as of today ReadWriteWeb says only has 0.4% take-up.

Lieb of Bump, posted a full breakdown of iterations and percentages of users, which is posted after the break. The key data is that 53% of users are on the very latest software update of 4.2.1.

• 4.2.1: 52.89 %
• 4.1: 27.50 %
• 3.1.3: 6.43 %
• 4.0.2: 3.36 %
• 4.0.1: 2.95 %
• 4.0: 2.94 %
• 3.1.2: 2.52 %
• 3.2.2: 0.49 %
• 3.0: 0.22 %
• 3.1: 0.21 %
• 3.0.1: 0.10 %
• 3.2: 0.10 %
• 3.1.1: 0.10 %
• 4.2: 0.09 %
• 3.2.1: 0.07 %
• 2.2.1: 0.02 %
• 2.2: 0.00 %

[Via ReadWriteWeb]