Apple on iPhone 4 Reception Issues: It’s the Software

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Apple addressed concerns over cell signal strength issues on the iPhone 4 in an open letter on the company’s Web site on Friday. The real problem, according to Apple, is the formula used to calculate the iPhone’s signal strength.

“Upon investigation, we were stunned to find that the formula we use to calculate how many bars of signal strength to display is totally wrong,” Apple said in its statement. “Our formula, in many instances, mistakenly displays 2 more bars than it should for a given signal strength.”

Some iPhone 4 owners have been complaining of signal loss issues when they grip their phone so the lower left corner of the device is covered by their hand. Users that experience the problem can watch signal strength bars disappear, and when they uncover the corner of their iPhone, the bars return.

The company said the problem with the formula used to calculate signal strength goes back to the original iPhone, which means users have always seen erroneous info about how strong their signal actually is.

“To fix this, we are adopting AT&T’s recently recommended formula for calculating how many bars to display for a given signal strength. The real signal strength remains the same, but the iPhone’s bars will report it far more accurately,” Apple said.

Along with updating the iPhone’s formula, Apple will be increasing the height of the first three signal strength bars so they are easier to see.

The signal strength issue has already spawned at least one lawsuit alleging the company intentionally misled customers and released a defective product. According to a class action lawsuit filed against Apple and AT&T in Maryland, the companies “sold defective iPhone 4 units, which drops calls and data service when held in a manner consistent with normal wireless phone use.”

The lawfirm of Kershaw, Cutter & Ratinoff has been hunting for iPhone 4 owners to include in its own class action case against Apple for antenna issues, too.

Assuming Apple’s assessment of the problem is correct, that’s good news for the company. “So there is no reception problem and no hardware problem,” an attorney familiar with this type of case told The Mac Observer. “If this holds up, the controversies and class action lawsuits go away.”

Apple plans to release a software update sometime in the next few weeks to address the problem. The update will be free and available for the iPhone 3G, 3GS and 4.

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?If this holds up, the controversies and class action lawsuits go away.?

As long as someone thinks they can get some cash out of this they won’t


Explains perfectly how their bars are off but not why holding the phone in a certain manner interferes with the bars AND reception. Haven’t there been reports of actual reception issues and dropped calls when gripping the phone across the black strip? Yes/No?

Changing the formula to improve the representation of signal does not improve the signal. If this was any other company I would be dubious about this “fix” and suspicious that the software update improves the perception of the problem but not actually fixing it… but hey this is Apple and we trust them 100% - right?


It just seems a little too convenient that it’s just a software issue.  I’m not convinced.

Bosco (Brad Hutchings)

Aw shucks Apple! Showing too many bars was the problem, not an external antenna that gets attenuated by moderately sweaty hands. Hilarious.

Just so you guys know… The lawyers for the various plaintiff groups will now focus on whether Apple might have deliberately fudged the bar display algorithm in order to give an appearance that its phones were getting better reception than competitors’ phones.

When a bumper case fixes the actual problem for people, it should have been a no-brainer for Apple to bundle one in with the phones and offer early adopters a freebee. Absolute no-brainer. It would have been a $2 million fix to what will become a $100 million problem.


Explains perfectly how their bars are off but not why holding the phone in a certain manner interferes with the bars AND reception.

Trust them 100%? No. I’ve seen Apple make too many mistakes over the years.
That said though, this would make sense. We’ve all been somewhere we don’t have great signal. Under those conditions putting your hand over the antenna could drop the call. If the meter is registering a much stronger signal than is actually present, then it would look like a fault with the antenna. It would also account for why the reports of the problem have been so spotty: it only hits when you have iffy signal, something you wouldn’t know by reading the iPhone’s meter.
All that is well and good but it’s quite possible that there’s more going on. This may be a smokescreen. It may be good copy while Apple is figuring out the real problem. No way to tell from here.

Bosco (Brad Hutchings)

Well will you take a look at this?!? Gruber agrees with your humble Bosco. Money quote from his translation of the PR letter:

We decided from the outset to set the formula for our bars-of-signal strength indicator to make the iPhone look good ? to make it look as it ?gets more bars?. That decision has now bit us on our ass.

Gotta go get more popcorn!!


It is unlikely that plaintiff attorneys would pursue any action for fraud, consumer fraud, or breach of contract on the grounds that the iPhone has misrepresented signal strength.  First, it would be difficult to prove misrepresentation because I don’t think that there is any accepted standard for calculating and/or representing signal strength, so Apple’s formula and methods for making such calculations are completely a matter of its discretion.  That being the case, there is no standard against which Apple’s extant method of calculating signal strength can be said to be false or incorrect.

The other problem is that with common law fraud, a plaintiff would have to show that Apple intentionally made a false misrepresentation of calculating or representing signal strength.  Once again, you have the problem, supra: there is no standard against which Apple’s method of displaying signal strength is false.  But even if you could find or devise some standard that a judge wouldn’t throw out, you still have to prove that Apple intended to deceive.  Apple said it made a mistake.  Unless it can be proved otherwise, there would be no intent to deceive sufficient to support common law fraud.

A final major problem for any lawsuit sounding in breach of contract, tort, equity, and/or consumer fraud law, which only requires that misrepresentation was incorrect and resulted in some loss of value from the consumer, is that there are no damages or would damages be so slight as to be nothing more than nominal.  People don’t see bars when they buy an iPhone, so any mistake or intentional misrepresentation with respect signal strength aren’t the basis of any bargain.  I suppose you could stretch and contend that the iPhone wasn’t working correctly, but it is a stretch.  And again you encounter the problem that Apple probably can calculate signal strength as it pleases, within reason.

Nor would any customer be perceptibly harmed in the use of the iPhone by the “incorrect” calculation and/or representation of signal strength.  Users of the iPhone make calls regardless of the bars.  If anything showing more signal strength than other calculations would show only results in people attempting to make calls that don’t go through.  Not much damage to anyone there.  I suppose you could argue that a user wasted a moment trying to make calls that couldn’t connect or that a user expected to be able to make calls that wouldn’t connect.  But once again, there isn’t any correct way of calculating signal strength, and neither is any way proving that any misrepresentation of signal caused someone to make or not make any particular call.

So I wouldn’t be surprised to see some plaintiff firm go down this road but not many, because there isn’t likely to be any significant recovery for the expense that the firm would bear in battling Apple’s skillful and ferocious lawyers.  I suppose the strategy would be a strike suit to get Apple to settle rather than afford the costs of kicking ass in court.


Aw shucks Apple! Showing too many bars was the problem, not an external antenna that gets attenuated by moderately sweaty hands. Hilarious.

Hey Bosco,

My G1 will go from -63 dBm 25 asu on my desk to -89 dBm 12 asu in my hand…. and my phone shows a loss of one bar when that happens.

Just saying that the attenuation happens on other handsets with a fully covered antenna…


Just saying that the attenuation happens on other handsets with a fully covered antenna?

I confirmed a signal drop on an older BlackBerry device when I covered it with my hands.

Bosco (Brad Hutchings)

@daemon… Nobody is disputing that measurable attenuation occurs with other phones. Just as nobody seems to be disputing that holding the iPhone 4 with moist hands shorting the gap causes significant attenuation. What the YouTube videos of this effect did was draw attention to a wider situation, one where Apple just denies and refuses to offer what would be inexpensive remedies.

@Nemo… And this brings me to Nemo… It doesn’t matter whether you think there is a standard for bars. Apple’s memo indicates that there is a formula that is commonly used in practice. AT&T has one that they recommend. And Apple will be switching to it. Which begs the question of why they got it so wrong in the first place. One reasonable hypothesis is that they did this intentionally for competitive advantage. A robust legal process will let the plaintiffs’ attorneys gather data to test that hypothesis.

What makes this great theater is that a terrible customer support policy is what is luring the legal attention that Apple is trying so desperately to deflect. If you just do right by your customers and not worry about the lawyers, you typically don’t have the problem. It’s one of those ironies of business that will sell a lot of popcorn this go around.


Here’s a thread about signal attenuation on the Nexus One….

Bosco (Brad Hutchings)

@daemon… A very fair point that other phones have somewhat similar issues. Two things…

1. My AT&T version of the N1 typically gets a drop of 4-8 db in a fairly low signal area (-97 db base measurement) when cupped in hand. I bought it two months after the report you reference. Anecdotally, it appears that HTC might have addressed the issue. Or maybe I just have awesome hands.

2. The exposed gap is the source of the iPhone 4G problem. Apple could handle it as a minor customer support issue, likely restricted to < 10% of their users who would know about it, notice, and complain to support. So they give out a couple hundred thousand bumpers and look like heros in the process while they come up with a longer term hardware fix they can roll into future production runs.


In its “Letter from Apple Regarding iPhone 4,”  Apple accounts for the iPhone 4 being held in a manner that covers both sides of the gaps in the iPhone 4’s external antennas.  Apple explains that isn’t the problem:

“But some users have reported that iPhone 4 can drop 4 or 5 bars when tightly held in a way which covers the black strip in the lower left corner of the metal band. This is a far bigger drop than normal, and as a result some have accused the iPhone 4 of having a faulty antenna design.

At the same time, we continue to read articles and receive hundreds of emails from users saying that iPhone 4 reception is better than the iPhone 3GS. They are delighted. This matches our own experience and testing. What can explain all of this?

We have discovered the cause of this dramatic drop in bars, and it is both simple and surprising.

Upon investigation, we were stunned to find that the formula we use to calculate how many bars of signal strength to display is totally wrong. Our formula, in many instances, mistakenly displays 2 more bars than it should for a given signal strength. For example, we sometimes display 4 bars when we should be displaying as few as 2 bars. Users observing a drop of several bars when they grip their iPhone in a certain way are most likely in an area with very weak signal strength, but they don?t know it because we are erroneously displaying 4 or 5 bars. Their big drop in bars is because their high bars were never real in the first place.”

Thus, the problem is one of miscalculation and and improper representation of signal strength, and not of the performance of the iPhone 4’ antenna system.  In other words, there is no hardware defect to fix, as Apple clearly says in its statement, supra.  Now, we will see whether Apple’s explanation will hold up to the rigorous expert examination that it will receive.  If it does, then those contending that there is a hardware defect in the iPhone 4 will be proven wrong; if it does not, Apple will be proved wrong and suffer the consequences.  But mere insistent statements that the iPhone 4 has hardware defect or that its reception degrades more than is typical when held at the gaps and/or that the iPhone 4’s reception degrades more than is typical when sweaty hand touch its antennas does not prove the truth of all or any of those statements, no matte how frequently or emphatically they are stated.  Now that Apple has offered its explanation and once it upgrades its software, rigorous scientific examination and only rigorous scientific examination can determine the truth, not the vehemence, frequency, or volume of those who insist that Apple is either right or wrong.  And for that scientific result, we must now all wait.


You are such a tool Nemo. Why don’t you go try and bill someone for your “legal opinion?”

Bosco (Brad Hutchings)

@daemon… Grasshopper, there are few sparring partners who can give us adequate preparation for the real battles. A wise warrior does not kill them off so quickly. Now go asphyxiate yourself in a closet and think about what you have done.


@Bosco… nice.


I know that I’ve prevailed in the argument when the opposition is reduced to insults, as you are daemon, or simply repeats already successfully rebutted arguments; that would be you Bosco.

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