Two apps may use different transformation tables. Check the birth data, stem, and whether each Hua Lu, Hua Quan, Hua Ke, or Hua Ji belongs to a natal, palace-stem, or annual layer. Save both rule tables and use one coherent system for a reading; do not cherry-pick the more appealing star from each app.
Save the app version and its full transformation table. A coherent reading uses one set of rules across all four transformations and clearly separates natal, decade, and annual layers.