Mellow and Concentration were discontinued from the official Interaxon SDK on April 12th, 2016. The official reason told to me being that they thought the algorithms were inaccurate.
After studying the "My Virtual Dream" paper, I spent a few weeks creating my own version of the mellow and concentration algorithms. However, I'm not 100% happy with the outcome and I think I understand why Interaxon withdrew their versions. If you would like to try them out, they are hidden in Muse Monitor. To enable them, go to Muse Monitor's settings screen and at the bottom, tap on the version number 10 times.
Once enabled you will find an entry on them in the in app help, explaining a little more about how they work.
I have shied away from this subjective matter in the past in favour of making Muse Monitor a purely fact based app, reporting only raw data aimed at researchers and curious minds.
The most common causes of connection issues are low battery, and the Interaxon Calm app connection to the Muse device first.
Interaxon unfortunately only let one app at a time connect to the Muse, and if you do not properly close their app, it continues to try to connect to the Muse in the background. To test if this is the issue, keep the Muse in front of you and watch the lights. When you power on, the lights will be pulsing up and down. Once the Muse is connected to an App, the lights will all go on. If you see that the Muse device is connected, but Muse Monitor is still searching, then the Muse has either connected to the Interaxon Calm app in the background, or possibly another device nearby. If you double tap the home button, you can swipe the Interaxon Calm app off the screen and this should close it fully and allow Muse Monitor to connect.
For when you're connected but then losing connection, low battery is likely the cause. There is a fault in the (in my opinion) with the battery charging light. When you plug in the Muse to charge, its lights indicate that the Muse is full after a set period of time, rather than when the battery is actually full. This means with a low power USB source, such as a USB2.0 laptop, your Muse won't be anywhere near full. To do a full charge, you need to leave your Muse plugged in to an AC power source for about 3.5 hours and ignore the charging light. After a full charge, most disconnection issue will be gone.