nfc - Can I access a device using Android HCE from a device running Android 4.3 (or below)? -


i have developed app emulates contactless smartcard using android hce , app accesses (reads) emulated card. both run on android 4.4 (kitkat) , above.

no develop reader-side devices run android 4.3 (or lower). possible access device uses android hce device api level < 19? not want use android beam feature.

no, that's not possible. default, 2 android devices (when held together) communicate in peer-to-peer mode. case if 1 or both devices support host card emulation. once android device established peer-to-peer mode link, won't try use reader/writer mode on same target.

in order permit android hce-emulated card visible (accessible from) second android device, second device must disable peer-to-peer mode capabilities , operate in reader/writer mode.

this android reader mode api (that seem use in reader app android 4.4). using nfcadapter.enablereadermode() flags flag_reader_nfc_a , flag_reader_nfc_b forces android act in reader/writer mode , disable peer-to-peer mode.

as api (or equivalent) not available on android 4.3 , below (i.e. before api level 19), have no means programmatically1 disable peer-to-peer mode. consequently, reader app on android 4.3 can't communicate android hce emulated card.


1) note disabling android beam in settings won't disable peer-to-peer mode either. disable beam capabilities run on top of peer-to-peer-mode.


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