This is an interview with the guys performing using four phones and Roli's noise app.

To read the interview go here:
https://www.blog.google/products/android/how-android-and-pixel-are-changing-way-musicians-create/

Interesting and the device is not going to be expensive either...

To read more go here:
http://www.valuewalk.com/2016/02/intel-android-phone-linux-desktop/

Rej the developer of Caustic wrote this on the forum for Caustic and it could be interesting if you need as low latency as possible.
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I just finished finished the rather long process of flashing the Google Play edition ROM onto my stock HTC One (GSM version aka M7) and it made a noticeable difference on latency. I haven't taken any measurements, but it's probably somewhere around what the second-gen Nexus7 is getting. (and probably on par with the Blackberry Z10)

Yay! makes it worth the hour I spent..Go Google!

Addition:
This when using the OpenSLES sound API, which is only in Caustic 3 
(and many other audio apps on Android), but not in Caustic 2.
Oh, and also I stress that this is after flashing Google's vanilla AOSP ROM.
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Yes of course I know about rooting the phone  but did not think or have been aware that you can change the Operating System of your phone to what different manufacturers use. If you did not know this I think it can be interesting to be aware of the possibility. What it means is that even if you have An Android version like for example Jellybean or whatever every company has it's own proprietary system on top of that.
 Well as a Samsung phone would come preloaded with certain applications and their own versions of things.
Almost all manufacturers do not care too much about lowering the latency but Google is trying and working on it so now the lowest latency you can get is with Google's own Android version that comes with their devices. So if your phone has the same Android version as on a Google device you can switch to the same preloaded version of Android...As Rej did. Meaning that your phone would as in the case above turn into a Google Nexus device.
Have been thinking about doing this but have not had the need to lower the latency on my device yet...
Feeling tempted as there is a coming more and more midi enables synthesizers but as I am not much of a keyboard player and being a little bit afraid of doing something wrong...
If I understand it, it is not exactly like rooting your phone... but kind of fucked up an earlier phone trying to root it so if I do not get suddenly very good at keyboards probably will keep my device as it is and hopefully make some money soon so I can buy a Nexus 7 instead with lower latency already.
Here is some more information if you find this interesting:
http://highonandroid.com/android-roms/what-is-aosp/

To read a positive review of the latest Android Operating system go here:
http://www.theverge.com/2013/11/4/5063490/android-4-4-kit-kat-review

Picked this up from the forum of Mr Nightradio. Just thought that it could be interesting as the lowest latency is on the Nexus devices from Google and think that it is soon going to be the same as the iOS devices. Who knows maybe with the Nexus 5?
To read more go here:
http://www.zdnet.com/nexus-5-the-seven-things-you-can-expect-from-googles-next-smartphone-7000021620/

The website Create Digital Music posted this with conclusion and expounding more on what they talk about in the video, so to read it go here:
http://createdigitalmusic.com/2013/05/why-mobile-low-latency-is-hard-explained-by-google-galaxy-nexus-still-android-of-choice/#more-29322

The other day this got posted on a website called http://createdigitalmusic.com it is an article/interview/overview by a man calle Ashley Elsdon that is behind the website-http://www.palmsounds.net/ 
It was a very interesting read for me as he talks about Palm OS and Windows Mobile music making. 
When these devices was used I was living in the Caribbean Jungle outside a village of about 150 people with an access of two telephones and electricity that was coming and going.
So for me to read the article was to read about forgotten history that never was part of my consciousness, and guess that it also holds true if you are young enough.
But what is interesting for making music on Android is that it gets mentioned in the article the existence of a program that makes it possible to run Palm OS applications on Android and that there is existing some pretty funky applications for making music.
So if you want to find some old school hand held freshness it is definitively worth to check out.
The program that makes it possible to run Palm OS apps is called Style Tap and is relatively expensive but then you get access to a lot of applications that is for free and possible to encounter around the internet.
 
So here is the link to the article:
http://createdigitalmusic.com/2013/05/retro-mobile-music-what-vintage-palm-and-windows-mobile-did-how-to-use-them-today/

Here is just links to Style tap and one of the better music apps for Palm OS:

http://www.styletap.com/

http://www.chocopoolp.com./

It is an interesting read you will not regret it...

Frank