This costs battery life, and to constantly evaluate download speeds would cost you cellular data.
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Almost 6 Years Now & iPhone Still Can't Gracefully Transition from WiFi to Cell
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This costs battery life, and to constantly evaluate download speeds would cost you cellular data.
But I am sure iOS is already doing this evaluation to a certain extend. It has to know when Wifi signal is no longer viable and switch to cellular. Perhaps it's just a matter of tweaking the threshold.
No. When you're out of range, no evaluating happens. It just switches to xellular
Believe it or not, even in the digital world, it's not so black and white. The same is true for being in range and out of range. There is a grey area between in range and out of range, as evidenced by the signal strength graph displayed by iOS.
iOS looks at signal strength and compares it to a predetermined threshold to decide if one is out of range.
And of course I am just guessing because I don't have access to iOS source codes. Nevertheless, the fact that iOS can display signal strength graph indicates that being in or out of range is not a black and white issue as you believe.
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The issue being discussed is switching to cellular when wifi is providing crappy bandwidth, not continually monitoring solely wifi bandwidth.
iOS devices can "ping" wifi routers using up and download speeds because data used is infinite. They cannot ping cellular as that would consumer user data.
That is my point.
The problem is the way the phone handles crappy WiFi reception. A better router would only push the dead zone further away not get rid of it.
I've had this problem too. Either I wait until I'm clear of the dead zone or, if I'm going to be there for a while, I turn WiFi off. Irritating but not a major issue and definitely not something I'd be willing to trade battery life for.
The easy solution is to just turn wifi off when you go where you only have one bar or where your router antenna can't reliably send more data than a ping. Turn it back on and your iPhone may stay stuck to the cellular signal until you walk back into better wifi coverage.
If the phone did this itself more aggressively, it would waste a lot more power turning on the cellular radio more often. So it's a trade-off.
If the phone did this itself more aggressively, it would waste a lot more power turning on the cellular radio more often. So it's a trade-off.
What you said does not make sense to me.
iOS always display both cellular and Wifi signal strength. There is no additional work necessary than what it is doing now. What I am saying is that iOS knows when Wifi signal is marginal enough to switch over to cellular. It's now just a matter of fine tuning the switch over threshold so that the switch over occurs before Wifi signal degrade to unacceptable level.
Again, contrary to your belief, I think the border of "has Wifi" and "has no Wifi" signal is not a thin line. Instead it's a grey area. The width of the grey area is determined by the predetermined threshold, for example between 0.5 and 0.9 on a scale where 0 is no signal and 10 is as strong a signal as necessary beyond which there is no advantage. In my example, if iOS raise the threshold of bad signal to 1.2 then the iPhone would switch over to cellular before the signal gets to be unacceptable.
Exactly.
No. RECEPTION and BANDWIDTH are NOT the same.
Reception is how well the device's antenna can access a network point, baring any physical or other interference. This means, I could be standing right next to an antenna and have excellent reception. Now put a cement box in the way, and reception will suffer due to this interference. What your iPhone does, is constantly measures RECEPTION, not BANDWIDTH. Even with perfectly clear RECEPTION, I still may not have great download speeds ...
BANDWIDTH is the measurement of download speeds and throughput by a network point. This is determined by the network point's adapter and network speeds on the whole. If you are the only device using a network point, you will have high download speeds. If multiple devices are plugging at a single network point, then download speeds will suffer, REGARDLESS of RECEPTION.
The best illustration of this is when you are at a sporting event with hundreds of thousands of people. You will have excellent RECEPTION because likely you are in an industrialized local where there are cellular towers, but will suffer from poor download speeds due to many people trying to utilize the same network point, thus BANDWIDTH will suck.
What the OP wants, is for iOS to determine which interace (wifi vs. cellular) has the fastest download speeds at any given time, and switch to that interface. As we just discussed, reception alone would not provide enough information for the device to make that decision. The phone would need to "test" download speeds of both interface, thus causing arbitrary cellular data to be used, because even with speed tests on networks, there is no such thing as a free lunch when it comes to data. Not to mention, continually testing bother interfaces would kill battery life.
What you say about "gray area" is correct, but as already discussed, increasing the "pickiness" of iOS wouldn't solve this issue. WiFi would just drop out at an earlier point, but the transition to cellular would still be the same.
The OP does raise a solid point, I'll give him that. But the sacrifice of data usage and battery usage aren't really worth it, IMO. Thus we have provided alternate solutions to accomodate his needs, such as a better router.
I think you meant "RECEPTION and THROUGHPUT" not "BANDWIDTH."
Bandwidth measures the total potential capacity. Throughput measures the actual IO rate at a given time.
Of course reception and throughput is not the same. For example, if you have a very slow broadband connection, and your Wifi router is on it. You may have excellent signal, but your throughput would still be slow.
That said, marginal signal can cause low throughput. That's why I suggested in my first respond that iOS could use marginal signal as a trigger to examine throughput and determine if it's low enough to warrant the switch to a cellular connection. And no, it won't affect battery life as you claimed. On the contrary, switching to a faster connection (in this case a cellular connection) will complete the task faster as opposed to dealing with dropped packages which wastes battery. And no, iOS already has the throughput information at its disposal, so no additional work needed to make this determination as you claimed.
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I'm sure you've made detailed measurements of all the different power modes for all the chips and radio transmitters in your iPhone, and the effect of various network switching strategies on typical device battery life.
My PalmPilot had great battery life. Changed the AAA cells once a month. Of course they didn't have to power any wifi, bluetooth or cellular radios back them.
This solution would be acceptable if there was a user friendly way of toggling WiFi on/off. But there's not. It too cumbersome to having go into Settings and shut WiFi off all the time. A very inelegant solution.
I'm sure you've made detailed measurements of all the different power modes for all the chips and radio transmitters in your iPhone, and the effect of various network switching strategies on typical device battery life.
Of course I have
No, like any opinion posted here, they are just reasonable guesses. As I mentioned before, I don't have access to iOS source code.
But there are enough information displayed by iOS to shows that it knows both cellular and Wifi signal strength, as well as possibly data throughput at any given time. That being the case, it would not be taxing to add some codes to make sure that if the data throughput drops below certain threshold and the signal is marginal and the phone is on Wifi, try switching to cellular. This checking only needs to be done when there is a data request, not if the phone is idle, so it should not affect battery life negatively. Furthermore, it appears that iOS is already doing a similar check for availability of Wifi network when there is a data transfer and the phone is on cellular.
Haven't we beat this dead horse enough already? It's not a router issue. A better router is just going to make this gray area further out. It's just going to extend the radius of coverage, but at the end of this extended radius, the same problem is going to occur. Plus, I've had this problem using my gen 4 AirPort Extreme. And this problem occurs other places, such as work and at Starbucks.
Very good point, currently I have to jailbreak to get this feature. I cannot believe it's taken this long and we still don't have easy access to toggles.
Also, there was a feature to seamlessly transition between WiFi/cell but it did not work well at all and was removed. Battery issues aside, it's detection capabilities were poor and as a result, it wasted many people's data.
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Almost 6 Years Now & iPhone Still Can't Gracefully Transition from WiFi to Cell
Sky has done this in a better way, when you instal sky's wifi app, which sounds like BT's, it installs a wifi profile, which automatically connects to and cloud wifi connection, no need to manually go into the app. Seamless.
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This is what I do. I only have wifi turned on at home or if I go into a friend/family's house or if I pop to A coffee shop that has free wifi otherwise I feel it's a waste having it on.
Takes me no more than 3 seconds tops to do this really. It's not cumbersome unless it takes more than a minute
I have the same issue, complicated by my ISP's providers way of providing WiFI roaming throughout the UK. Basically one can download their app, BT Wi-fi and theoretically one can log on to any BT WiFi router.
The problem is that the app is a smelly, smoldering pile of manure because it requires one to open the app and log in manually each time: Imagine that you walk from your house to a bus stop and want to check the bus schedule. At your house your on your own internet, then 3G as you go out of range, but then right in the middle of downloading the bus schedule you come into range of another BT WiFi router. Now 3G stops and then the WiFi networks waits for your manual login via BT's accursed app. So you press the button. And then walk further to the stop only to find your out of range of the previous WiFi but in range of another BT router. Go back to the £^&$%!&^%$& BT app and log in manually ... again. Repeat endlessly. Do not pass GO. Do not collect $200.
Bloody annoying.
Sky has done this in a better way, when you instal sky's wifi app, which sounds like BT's, it installs a wifi profile, which automatically connects to and cloud wifi connection, no need to manually go into the app. Seamless.
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This is what I do. I only have wifi turned on at home or if I go into a friend/family's house or if I pop to A coffee shop that has free wifi otherwise I feel it's a waste having it on.
Takes me no more than 3 seconds tops to do this really. It's not cumbersome unless it takes more than a minute
Takes me no more than 3 seconds tops to do this really. It's not cumbersome unless it takes more than a minute
Yes, but you still need to repeat those steps to put it back on. Plus, the small delay it takes to find your preferred WiFi network.
I know. It sounds trivial and I would have expected this clumsy WiFi to cellular transition in iOS 1 or 2, maybe 3, but the iPhone has been out 6 years. They have well entered the stage of polishing the little things, but this has not been one of them. And even Apple knows this is a problem by the presence of the "WiFi+3G" toggle in the iOS 6 beta. But, as a long time iPhone user, it customary to wait years for basic functions.
That's one of the main reasons I switched from my Samsung Galaxy S2 back to the iPhone. With the Samsung, I'd leave the house, turn wifi off, but half the network dependant apps would not work. I'd either have to restart the app, turn on/off airplane mode, or sometimes even power off/on the phone to get things working again. Never had that issue with the iPhone 4 or now with my iPhone 5.
Almost 6 Years Now & iPhone Still Can't Gracefully Transition from WiFi to Cell
The small delay in finding the network would be there even if there was a quick toggle, so that's not really an issue.
The Wifi+3G will probably be in iOS 7, look at panorama, that popped up I. A beta for iOS 5 then disappeared until iOS 6, they probably realised it wasn't ready for primetime.
We don't have a toggle and it doesn't really bother me as it doesn't take too long to let it bother me. A toggle will save me 1-2 seconds, wow that's.... Not really worth it. But each to their own.
The small delay in finding the network would be there even if there was a quick toggle, so that's not really an issue.
The Wifi+3G will probably be in iOS 7, look at panorama, that popped up I. A beta for iOS 5 then disappeared until iOS 6, they probably realised it wasn't ready for primetime.
We don't have a toggle and it doesn't really bother me as it doesn't take too long to let it bother me. A toggle will save me 1-2 seconds, wow that's.... Not really worth it. But each to their own.
It's not really that hard. You could do it by defining a minimum transmit rate (which is auto-negotiated with the WiFi hotspot) before it switches over, a maximum threshold of packet loss, or both.
I've actually found that the latest versions of Android are better at doing this than they used to be. They have a new WiFi setting which is "Avoid poor connections".
It makes the device switch over to cellular sooner than it otherwise might. It does this as the signal gets weaker when going out of range rather than maintaining a WiFi connection which is functionally useless.
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Oooh. Cool. Not sure Apple likes letting people choose on things like that though.