RSS Feed

Posts Tagged ‘iOS’

  1. Sharing your screen

    March 7, 2016 by Robin Englebright

    At the HEA arts and humanities conference  on the 3rd March 2016, Vikki Haffenden presented her research into improving the student experience in workshop sessions.

    When teaching Vikki demonstrates really intricate settings on knitting machines and close up work, to University of Brighton Textiles students,  and it can be hard for the students to see. After much experimentation she settled on using the camera on an old iphone4S in a chest harness to stream video to an appleTV and then onto a 32″ TV screen, so students can see even if their view is obstructed, and in fact can see in more detail as the image gets magnified.

    To test the decisions Vikki made the session then moved to a hands on workshop, comparing a range of screen sharing technologies and drawing out the pros and cons of each.
    We started with a quick Poll using PollEverywhere to gather thoughts from the delegates on potential uses for the technologies.


    PollEverwhere performs the function of the older style voting buttons, but using mobiles to access the poll either through the website: or by Texting BRIGHTONHEA to 020 3322 5822.

    For our demo the question was “How do you think you might use screen sharing for in your teaching?””

    We then spilt into two teams, to see how easy it is to set up the kit, as this was one of the areas Vikki identified as important, if it’s too tricky to set up, or unreliable it leads to a bad experience.
    Team one (team Vikki) used Vikki’s iPhone in a chest harness streaming to an apple TV and screen combination.

    Team two used a Go Pro with a head harness (because a head harness is way funnier) streaming to the Go Pro app, connected to a projector by an adaptor cable.

    GoPro app

    Both teams had the kit up and running with minimal support, and both setups seemed to offer similar functionality. The GoPro has more settings and a removable sdcard which could be a benefit, as video recording takes up loads of memory.
    There are some interesting points with both devices  that need consideration however.

    When using the appleTV setup both devices must be on the same wireless network. This means a personal appleTV setup carried to a teaching space is ok, but slightly trickier is one leaves the device setup in a room, as it will require it’s own eduroam account, which may not be popular with IT depts. In order to setup an eduroam account one needs to connect the apple TV to a modern mac, and run the configurator app, which is a bit of bother.

    The GoPro bypasses the problems of requiring an eduroam account by acting as it’s own streaming server, and in order to connect the app one has to first connect to its wifi network. The downside of the GoPro is that it streams to a mobile device, which is slightly harder to then connect to a screen, we used an adaptor cable, and to be honest were quite surprised when it worked. There is a way of accessing the GoPro stream via a PC web browser, but it seems quite a faff.
    Our next Demo failed, probably due to the conference centre wifi, but I’m not totally sure.
    I tried it again as soon as I got back to the office and it worked fine.
    Reflector2  works in a similar way to the appleTV, screen sharing requires both devices to be on the same wifi network, and the person sharing their screen has to swipe up to reveal their “Airplay” settings, and then pick the device to stream to, The upside of reflector is it only costs around £10 and runs on your laptop, so if you already take a laptop to your lectures/demos, it doesn’t require much other work. It also (in theory) allows android (and windows phone) users to share their screens, although I’ve had no luck with my Nexus 4 or Nexus 7.
    A big difference is that it allows multiple screens to be shared simultaneously, we’ve tested it with 9 devices before it all went wrong.


    As an added bonus individual shared screens can be recorded on the laptop, I’ve no idea what would happen if you tried to record 9 simultaneously, but it would probably be ugly. Whilst you could have multiple mobile devices streaming from their cameras, Reflector seems to lend itself to sharing sketches, or photographs to compare and contrast.
    After spending most of the session looking at sharing detailed work, we moved to sharing at a grander scale.
    The SWIVL device is a small motorised base unit that can hold an iPhone, or iPad, and will track the movements of a presenter who wears a small wireless lanyard.
    This lends itself to more expansive demos, maybe where those watching are viewing remotely, so we paired it up with an iPhone running Periscope, which streams to the web.
    It is worth noting that whilst I’ve found the cheaper basic appleTVs work better in conference mode setting  the new devices have a periscope app, which could make connecting easier…

    We closed the demo using Nearpod which allows the presenter to control the screens of the delegates whether they are in the room or not, and push slides, links questions and activities out to them, and then share the responses back.


    For University of Brighton Folk on Monday 14th March 12-1 in G4 I’ll be running a Lunch hour app swap, where we’ll revisit the hands on part of the session, and I’ll bring along:
    A visualiser, an AppleTV and GoPro, Reflector2, SWIVL, Periscope and Nearpod.
    …and of course there’ll be a chance to share your ideas and favourite apps.

    See you there.

  2. Power complex

    May 13, 2014 by Robin Englebright

    At our app swap cafe today we shared some top tips for iOS devices, Beth previously shared a tip that charging your iPhone in Airplane mode made it charge faster… However at the event Beth had a bit of follow up – that the tip might have been an urban myth.

    Later the topic of closing apps on iPads as a way of prolonging battery life came up, which I was pretty sure didn’t make much difference.

    So I thought I’d investigate and maybe find the truth.

    An iPhone 5S has a 3.8v 1560 mAh Lithium ion battery, and can charge at up-to 1 amp, limited by the charge control circuits in the phone, battery condition, battery temperature and the rating of the charger attached… so the very fastest it could charge is about 1.5hrs (1.56 aH/ 1 A) However we probably won’t have optimal conditions, so for our example lets assume we can charge the device in two hours.

    Now the question becomes can we significantly drain the battery over two hours?

    Obviously if you sit around watching Netflix on the phone during the two hours the battery won’t charge as fast, and I’m assuming putting the device in airplane mode isn’t just a way of preventing user activity, so to test a likely situation I rashly assume that the phone won’t be used when charging.

    In this case the draw on the battery will come from active apps, and those running in the background, which touches on our second “myth” that closing apps will prolong battery life.

    The developer guidelines for iOS indicate there are 5 states for an app, of these two have potential to use power.
    If the app is “Active”, it’s in the foreground AND recieving events,


    If the app is executing code in the “Background”.

    Apps usually only briefly pass through the Background activity state to close threads when switching between apps, unless they have permission to run in the background.

    However iOS is dead smart at managing its resources and is happy to move inactive apps to a suspended state, which keeps them in memory but not executing any code, and if memory runs low the system may close suspended apps to provide resources to the foreground app.

    The upshot of this automatic app management is that iOS will suspend apps that aren’t actively being used, so the power draw from these apps is negligible.

    The only apps that may be drawing power are active Background apps, and the only ones affected by switching to airplane mode are those that use the the wireless, carrier connection and bluetooth.

    The behaviour of apps in Background can be set in:

    Settings > General > Background App Refresh.

    and indeed here it does state that turning off background refresh may help preserve battery life. I was a bit surprised to find I had 25 apps using background refresh.

    iPhone Background app settings

    So in summary switching to airplane mode may well make your device charge faster if you have lots of apps set to Background refresh, but probably not by much.

    Closing apps manually is going to free up memory, but if they are suspended will not change power consumption.

Skip to toolbar