React Native on iPhone Duo React Native has no fold or hinge API . There is no , no hinge event, nothing that tells JavaScript the device is folded. As of this writing no React Native or Expo release has shipped iPhone Duo support. The good news is that the two things that break most often — resizing and safe areas — are already solvable with libraries you probably have installed. Work in two tiers. Tier 1 — works today, no native code Safe area insets, handled per edge This is where React Native apps break on iPhone Duo, and it is worth being blunt about why: the safe area is asymmetric here…