With iOS 4.0.1, Apple has rejiggered the the way that your reception is shown on the phone, claiming that the formula they used previously was all out of whack. So, how does the new way of crunching the numbers differ from the old? The folks at Anandtech used the iOS 4.1 beta — which uses the new formula — and compared it to their results from iOS 4.0.
As you can see, previously bar 5 was enormous, and bars 2 and 3 were tiny. This meant that the phone was much more likely to show full reception, and could easily jump from 1 bar to 5. The new version of the OS as a much more even split, and overall covers a wider range of signal strengths.

Is anyone actually buying this rubbish? What about my other AT&T phones that show 5 bars? Are they wrong too???? WTF APPLE??
Unfortunately, each cell phone maker decides how it wants to display cell phone bars. There’s no standard. So, different cell phones can show different amounts of bars.
I want a pie chart. Who doesn’t like pie?
I love pie! I could definitely go for some iphone pie right now…
and ‘Steve’ you cannot compare other phone manufacturers to Apple, thats like comparing Apples to Oranges!
I really think Apple deliberately had the old formula solely for the sake of AT&T’s sub par network. Let’s face it, having five bars showing does not change the way the phone works, it only makes the user think they’re in a high signal strength location.
Exactly, just bcuz it shows 5 bars doesn’t change the fact that AT&T has a terrible network. I’ve been with all major U.S. carriers and AT&T is second TO LAST! VERIZON PLZZZ HURRY UP AND CARRY THE IPHONE!!!
Great…now we can’t even trust our phone signals now when we see bars on the screen, the deceit!! What’s this world coming to?!
will someone who knows please answer this question…
what is with the range between -113 and -121 db? that is zero bars. does the phone think there is no signal and hang up (drop calls)?
i just want to understand what’s going on.