Kroger is reportedly awaiting FDA approval for an app that would act as a go-between, connecting rapid test kit with lab.  Why?  It is another kroger trap.  Kroger apps do not belong in your device.  

If an app or some other means gets your test result to you faster, that could be useful, just not if it invests your device with kroger malware and tracking.  You and yours will be better off without it.