I have asked myself this question so many times now and now that I want to buy my own air purifier (I ordered one for my parents, I think the AC2887/10) I have come across the two models that interest me again.

Like this! I asked "Philips" directly and a member of staff confirmed that the Philips AC2889/10 has the app function (although the comparison picture says that the other one does too... But since my parents don't need that, we never checked, of course). And that is apparently the only difference.

Quote from the support chat with Philips: "The main difference here is actually that AC2889/10 can be controlled with the AirMatters app, otherwise the models do not differ in terms of other performance."

The AC2889/10 can be controlled (=stupid!) via app. This Philips has now just finished as test winner in K-Tipp. My criticism: the water tank should be bigger. The light source (coming from the switch) can be a bit annoying at night.

CONCLUSION: I have certainly owned and tested more than 10 humidifiers. I would buy this model again.