Of course what I'm really wondering is what app, doesn't hiccup, doesn't ever hang, works on every tablet type. Come on. You know that doesn't exist. Not now and probably not ever. Generally if you need perfection, you should probably be using a MixWiz. (Much better than the possible problems with all the digital mixers.) But I'm not going back. I'll just live with all the quirks.
Hiccups occur, no doubt. Certainly not perfect. Stability differences do exist across the varying apps & versions, OS & versions and hardware that many have read about and documented on this forum. I state from experience as an owner/user of MF, X-Mix, and SLRemote that any hiccups of MF/DL1608 far exceeded any combined hiccups of X-Mix & SLRemote combined.
It would not just be a contention, but factual, to state that the history of the Mackie Master Fader app version releases has had the greatest burden upon the users in an any attempt to utilize existing hardware, comparative to other manufacturer apps. Exacerbating the situation is the MasterFader one size fits all approach and lack of PC/Mac or Android offerings.
To be fair and factual, X-Mix current version now requires iOS 6.1, however previous X-Mix on iOS 5.xx is still fully compatible with an X32 product running FW version 1.5 if needed or by choice.
SLremote original is iOS 4.3 minimum compatible. And of note, SLRemote AI is 6.xx, and UC Surface is 7.xx minimum.
Yamaha, Roland, and A&H apps are all iOS 5 compatible, allowing for use of an iPad One. A&H iLive MixPad, OneMix, and Offline apps are even iOS 4.3 compatible. And of particular note, A&H iLive MixPad is a $99.99 US Apple App Store download.