Miracasting from Android devices

Miracasting from Android devices

In parallel with the Tablets in Teaching project, we have also been evaluating various Android devices as alternatives to Apple iPads.

With the advent of Android 4.2, it has been possible to wirelessly project an Android screen onto an HDMI display.  By this we mean that anything on the mobile device’s display is replicated on the remote display.

Whereas the Apple AirPlay solution requires access to an established network to function – with all the procedural problems that can entail – Miracasting sets up its own mini-network between the mobile device and the receiving dongle plugged into the remote display.  This is more hassle-free than AirPlay and is independent of the podium PC in a lecture theatre – modern podiums have an HDMI input socket which can be used if you don’t have direct access to the display’s connections.

We tested two source devices and two receivers.  Both sources worked well with both displays and were able to display wirelessly whilst running live BBC iPlayer over WiFi.  However, the phone’s SIMs had to be turned off to force it to use WiFi, otherwise iPlayer slowed down to a crawl.

We used the second source device to attempt to hi-jack the remote display.  In no case did this succeed, so even if students have Miracast-equipped devices in the lecture, they may be able to see the receiver but not connect to it.

We used a tablet and a smartphone, with each of the two receivers.

	Google Nexus 7	Butterfly 920
Android version	4.3	4.2.1
Connectivity	WiFi, Bluetooth	WiFi, Bluetooth, 2 SIMs
Native display	7”, 1920 x 1080 HD	5”, 1280 x 720
Remote display 1	22” Iiyama HD widescreen monitor
Remote display 2	Podium HDMI connector to HD data projector
Remote display 3	42” Brockington study pod HDTV

 

The two receivers were a Phone2tv dongle (eBay, £32) and a Netgear Push2tv dongle (Amazon, £60).  In both cases a USB connection is needed to provide power to the receiver and both had extension cables so that the dongle did not need to be physically attached to the display.

Of the two, the Phone2tv receiver was slightly quicker to set up but the Netgear was slightly better at buffering the incoming data stream, so played with fewer jerky interruptions.

Both devices carry audio as well as video.

 

In use, the HDMI and USB connections are made and the Wireless Display settings used on the source device to initiate the connection.  In the example shown, the Aux HDMI input has been selected to feed the graphics through to the data projector.  The other sources – PC, Laptop, Visualizer and Blu-Ray player are still available and can be selected as usual.

The wireless display link works up to at least 5 metres from the receiver, giving the presenter the freedom to move around and interact with the class.