SYMPTOM
A user can define custom colors for a heatmap widget by changing the threshold of the metric in Editable mode.
Note: If there are more than 1 metrics in the heat map grid, the thresholds cannot be applied to the first metric. See the first workaround in tech note KB273192: The color of the Heat Map widget cannot be changed in Presentation mode in MicroStrategy Web 10.1 for more information.
Below is an example in Strategy Web 10.2 of a heat map widget with custom thresholds:

However, in Strategy Mobile 10.2, the defined colors are not considered and instead the users sees the default red to green scale as shown below:

STEPS TO REPRODUCE

CAUSE
This is an identified defect in Strategy Mobile 10.2.
ACTION
This issue is fixed in Strategy Mobile 10.4. Upgrade application to 10.4 to take advantage of the fix