As many other reviewers have pointed out, the app is incredibly frustrating. With an Ecodan air source heat pump, you’re able to see the temperatures in multiple parts of the system in the app. However, it’s near impossible to analyse what’s going on. For example, the axis scales are fixed, with no option to zoom in or out. Often the vertical scale range is so large that you can’t see any temporal trends. You’re only able to view sub-hourly data in one hour fixed intervals (why!?). There is no option to query individual data points in a plot, or view tabulated values, or even current values for all parameters being logged. The list could go on. The app really seems like a token effort, and it doesn’t seem like it would take much to vastly improve it.

Good points:1. The app works and seems stable.2. There is some good information available in the module view and reports.3. Setting changes made on the app reflect on the system.4. You can make many changes to the system settings from the app.Improvement items:1. System changes need to be checked to ensure the changes have been accepted by system.2. Reporting should have all temp settings in one report - flow, return, room temp, outside temp and be able to be viewed within the jour period, hourly, 7 days etc. otherwise it requires moving between reports to get all temp data - suboptimal.3. Module view on an iPhone - the back and refresh buttons are so close to the swipe line that often in accessible (out at the top of the module view perhaps?)4. The app is not that intuitive until you have learnt your way around the system, then it makes sense but is clunky. Ideally having better define and easier access to key settings would be preferable. Future:1. A report that assessed current settings compared to an optimum configuration would be ideal. Think how Mitsubishi would benefit if it assessed individual / regional / global ecodan data and could provide a suggested ideal, energy efficient optimum configuration (including the potential energy that could be saved), that a user could simply tailor based on their local situation / needs? 2. Needs to be compatible with all ‘now’ standard smart interfaces (HomeKit, Alexa etc etc)

Trying to use the app with a heat pump is a very frustrating experience.As many have pointed out the app will not let you look at any meaningful data trends as it uses some polyline function on the data to make the curves look "nice" which makes the displayed data trends unusable.Hourly data cannot be viewed other than for a single hour. You have to tap through and write the numbers in an Excel sheet yourself to see whats happening in the system.Worst of all the home page status for DHW and Heating does not reflect the actual status on the heatpump, I.e. the heatpump itself has three modes for DHW: operating (the play icon), prohibited (the circle with the diagonal line) and timer (the clock) mode, whilst the app status page has only2 buttons "Auto" and "Heat now"! Why the app uses a different control logic and different user experience as compared to the control panel on the heatpump is anyone's guess.Mitsubishi, if you are reading this, may I suggest you simply copy the same identical controls, display and settings from the on-device display? Literally just copy it 1:1 to the app with the hard function keys replaced by soft keys on the app. This will make it super intuitive to use and the user can reference the existing manual that came with their heatpump, both for the app and for on-device control.

Reently went on holiday - don't the holiday mode as it has never worked for us, so change the settings to what we want while we are away. The programme looked right but heating came on as if we were at home - didn't realise this for several days, so was heating the empty house at the coldest time of year. No matter what I did the app just igmnored any programming and continued to use the previous settings so every day I had to set alarms and manually change the temperature. I even deleted the programme and set up a new one - still no change. Now at home and having to use the master switch to get the heating to come on or change at the time and temperature we want. totally unreliable app whch is such a shame. Developers don't seem intersted in updating and you have no choice.