I'm not sure how to call this KPI... I'm sure there's a name for it... I name it success indicator :) I was thinking it would be nice if one could define a little formula to define and see the success or "system health" (if one thinks about a server) of the current website, app, server,... with just one number. I like simplicity :)
nb_unique_visitors * 1.5 + nb_pageviews / 1000 + (nb_actions - nb_pageviews) / 1000 + nb_users * 140 + nb_revenue + nb_goal_conversions. Instead of looking at these 6 facts (or more depending on the formula) one could have a look at just one number and see how the website, app, ... is doing. This could be especially nice when viewing this number eg on a watch close to the time or as a separate app, as a widget on the home screen of a smartphone like Android, .... One could display it in all websites dashboard, Live tab plugin, ...
Eg for all websites dashboard it would be really nice as one would get an overview of how a website is doing in general without having to customize the all websites dashboard and without having to add many columns. Clicking or hovering a KPI would show the formula and the single metrics and how they changed to the compared period.
One could also create multiple such success indicators and create a dashboard view that shows big numbers on a TV etc... similar to Dashing
We could provide some predefined sets and let users tweak them as it will be hard to create good indicators. Eg for B2B shops, B2C shops, B2B website, Intranet, ... Maybe there are even some formulas available.
It is similar to New relic query language but simpler and could be a first step towards such a query language this as it shouldn't be too hard to implement.
In another version it could be possible to filter them by segments etc to answer insights questions like "How many users are currently active via iPhone by defining
nb_visitors|deviceName==<a class='mention' href='https://github.com/iphone'>@iphone</a> . This number could be also added as a widget in the dashboard etc.
Having a simple API for this the community could very easily build apps for various devices to show these indicators very simple.
When reading this I directly think "Calculated metrics" which is a feature created by Google Analytics recently: https://support.google.com/analytics/answer/6121409?hl=en
Lots of great examples in this blog post: http://www.lunametrics.com/blog/2015/10/22/calculated-metrics-universal-analytics/
--> so maybe we need to build "Calculated metrics" UI and functionnality in Piwik?
It is very similar. Idea would be just to have like one indicator for your website, mobile app, server, ... that would be treated in a special way eg shown in all websites dashboard, the community could with a simple API build very simple app for watches and other smart devices so one can see with one view how the site is doing.