Up until a week ago, if you asked 10 Windows Phone users why they didn’t have an option for persistent WiFi, at least 9 of them would have answered, “because it will kill you battery stupid”. I will admit that up until I found the iHeartRadio trick, I was one of those 9 people. But I can tell you as a matter of fact, it is simply not true and can be filed away with the likes of; if you don’t brush, all your teeth will fall out tonight. Or, if you don’t drink your milk you’ll get rickets.

I ran a series of tests on my Lumia 900 and discovered that, by a slim margin, keeping WiFi active persistently while your LTE data connection is also active, can in fact SAVE you battery power. The reasoning is simple enough. With persistent WiFi on, you LTE connection will remain in a idle state while your phone is awake or asleep. Sleeping LTE uses very little power and a reasonable WiFi connection uses much less power than active LTE, so one radio balances out the other. Almost sounds like it was meant to be.

I also ran some tests with my non-SIM HTC Surround. As the phone has no access to a data connection it was easier to prove that WiFi was in fact working while the phone was asleep. I left WiFi running on my Surround for nearly 3 days, 71 hours actually. Total drain over that period was 86% or 1.21% per hour. Sounds like a lot, but take note of a few things. The Surround has a meager 1230mAh battery. So running the same test on a L900 would have dropped about 53% over three days. And that was with one “push” email account, two Background Tasks, Location services enabled, and a crapload of installed app updates (I still have 150 apps on my Surround) that Marketplace probably never got a chance to check as I previously only had my phone connected sporadically over WiFi. I ran one additional 24 hour test with my Surround, with persistent WiFi off and on to measure the difference. With WiFi turned off I dropped a total of 36% over 24 hours, or 1.5% per hour. Keep in mind that the Surround battery drains much differently than the Lumias. In previous tests I discovered that my battery would drain quickly from 100% to about 85-82%, level off over the mid-range, and then drain more quickly in the last 20% or so (with Battery Saver disabled). So ignore the actual number and focus on the difference. With persistent WiFi active, my Surround dropped 31% over the same 24 hour period. Yeah, a little lower with WiFi on vs. no connection at all. I’m confused too. Let’s just call this a tie.


So as we now know that persistent WiFi does not kill your battery, and may even help to extend your battery life, why don’t all Windows Phones have a option to keep persistent WiFi on. Why did we have to discover this via a bug in a few apps. I can only think of one possible reason. Carriers don’t like WiFi. They may talk about providing you with WiFi hotspots. and suggesting you connect to WiFi whenever possible. But the truth is all they are doing is trying to condition you to consume more and more data, so that when you don’t have a WiFi connection, you will be using more of your metered allocation (face it, unlimited is all but gone) and with any luck, may even go over your monthly limit. That’s good for Carriers and bad for everyone else.

When Windows Phone was released, Microsoft was fighting an uphill battle with Carriers. As much as Carriers desperately want a third ecosystem to keep Apple and Android in check (and use it against those mobile behemoths) they used their twisted reverse psychology to make unreasonable demands on the likes of Microsoft and Nokia. I can only imagine the 800lb Gorilla pounding its fists in private and biting so hard on its lower lip that it bleeds. And while my guess is all Carriers would prefer WiFi to be outlawed, only one or two would have the necessary clout to make unreasonable demands, even while portraying themselves as a premier partner. With one such Carrier having 15% of the World / 52% of the US Windows Phone Market, according to the Outsider app (previously I’m a Wp7, and I know, anecdotal), it starts to become clearer who is moving the levers behind the curtain.

So how would persistent WiFi work. This is how I would envision the new, improved Windows Phone WiFi. When there was no active access point available, WiFi would sleep as it does now, using virtually no power at all. If you woke your phone up and a WiFi access point was available, your phone would connect, and remain connected as long as you were within that access point range. Wouldn’t matter if your phone was awake, plugged in to a charger or sleeping in your pocket. For example, you are connected to WiFi at home, walk out the front door and get in your car. As you pull away, you lose your home access point signal and WiFi goes to sleep. If you turned your phone on in the car it would connect to your car’s WiFi access point (my future world), but otherwise you are at the mercy of Carrier data for your short trip to Target. After you walk into Target, you get a message tingle and turn your phone on to check the text or email. As soon as you do, you connect to Target’s free WiFi network, and will remain connected till you get out to the parking lot. Next stop or store, same scenario. Virtually connected to WiFi all of the time, so Skype and other VOiP services become more practical for everyday use. And good news for those pesky secured WiFi networks that require you to login each time you disconnect. Of course there will be instances where you will have a need for that 20Mbps+ LTE speed for whatever reason. So you override the current available access point with a simple tap. But the next time you turn your phone on in a new access point’s range, WiFi takes over again. Now that’s good for everyone, except the Carriers. Oh well.

Come on Microsoft, the cat’s now out of the bag. There is no place to hide. You have run out of excuses for not making persistent WiFi a feature on every Windows Phone, regardless of version. It’s time to push back and do the right thing. Carriers be damned. Customers deserve the right to maintain a constant connection to free, abundantly available WiFi signals. I challenge anyone to explain to me why a persistent WiFi option should not be made available, either via a Marketplace app (we already know that apps can inadvertently trigger persistent WiFi) or as part of the WP7.8/8.0 refresh. In yesterday’s Truth article, Joker added a comment indicating that Microsoft has rectified this issue with something called  “Connected Standby” for Win8 and WP8. Let’s hope that’s accurate. In the meantime, if an update for iHeartRadio does show up on your phone tomorrow, be sure to ignore it, unless you want to lose access to this newly discovered feature.


  1. I’m not usually the one defending MS these days for their WP mis-steps but the idea that at&t or other carriers somehow influenced the design of the OS to suit their needs is ludicrous, when the reality is carriers worldwide since WP launched have been the platforms worst enemy. If they really went to all that trouble they would have been pushing WP with all they have, but the reality has been that they have done all they could to kill it.

    Cool story though. /s

  2. Not suggesting any Carrier lifted a finger to help WP. But based on WPs meager marketshare Carriers make the rules with a take or leave it kind of attitude. Reality is they are trying to hold on to something that is shifting. Like believing landlines will be relevant in another 5 years. People are tired of paying exorbitant fees to Carriers. And while everyone will eventually have a Smartphone, not everyone will have a cellular plan.

  3. Interesting idea but I don’t know how realistic this is. Most of the places I go don’t have WiFi or the signal is rather weak. IIRC WiFi searching sucks battery hardcore because the 802.11 spec was never designed for mobile? But then again WP7 seems OK on WiFi so maybe that was solved. I know that the network stack in Win8 is highly optimized for data connectivity even in sleep states so this will not likely be an issue going forward.

    I certainly don’t see a carrier initiated data conspiracy here, though. Just who are these people who burn through 5GB+ of mobile data every month? I barely average a 1GB on a family plan with 5 smartphones. And don’t talk up “free” public WiFi too much; would you really rather share the local coffee shop’s 768Kb DSL line with 50 random people than use a bit more juice to get you own fast, secure 4G connection?

    I like how aggressive you are about seeing WP improve but I think you are off the mark here. Security concerns alone would preclude me from ‘persistently’ connecting to any random WiFi within reach. The potential battery drain of my phone spending 8 hours a day trying to reach the AP 3 floors up is just as worrisome.

  4. Great article as usual Jim! There was a homebrew app that released yesterday which keeps wifi ON. Can’t remember the name but check it out.

  5. Good points Bob. I think when retailers, not just coffee shops and McDonald’s, realize how much information they could collect while customers were in their store using their free WiFi. Knowing how many folks were browsing Amazon.com, or their closest competitor, while shopping would probably be a nice tidbit, and without having to pay Gartner or Neilson big bucks for information. Sure, some may have a problem with this, but the FREE thing (for a price) sucks in the masses. Just ask Google how that works.

    Hey Xsever, I did read that thread over at XDA and left a couple comments. Seems like the dev is still having problems keeping the connection active, and may be consuming battery in an attempt to manage it. Once its a bit more stable I will give it a whirl. Maybe iHeartRadio could make us a toggle on/off app.

  6. @ Jim

    I jumped ship from iHeartRadio to Skype since the Skype method requires less user interaction. I just launch the skype app, let it auto sign in and then press the windows button. The radio app requires you to start a stream and then pause it and then the windows button.

  7. Xsever. Hmm, but with Skype you have to keep the app running in the background. With iHeartRadio, I can completely back out of the app. And I have even run a video to remove the music stream from the volume control. WiFi remain on without anything, including no Background task.

    May not matter that Skype is running, but I started my last Truth testing last night, starting with multiple tabs open in IE and following up with open pages in multi-task view. If last night’s teat is any indication of the final results, then I think we have another problem Redmond. Just sayin.

  8. What you mentioned about the radio app is interesting. I wonder which if Skype in the background consumes lots of energy compared to completely backing out of the radio app as you claimed.

    More room for testing I guess!

  9. From my test last night, using Skype or iHeartRadio to keep wifi ON consumes the same amount of energy.

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