Setting up an environment for testing DPP

Hi,
I'm currently setting up an environment for testing the WPA3 "Easy
Connect" / DPP feature and I have some questions and, unfortunately,
already some issues.

My environment will use:
   - A Raspberry 4 based on Ubuntu for the AP
     Following the README-DPP (under WPA2_supplicant directory), I
rebuilt "hostapd" with DPP (CONFIG_DPP=y) and interworking
(CONFIG_INTERWORKING=Y).
   - A Ubuntu system running in a VM on my laptop using a Edimax WiFi
dongle as client.
     On this system, I will rebuilt the WPA_supplicant with DPP (CONFIG_DPP=y)

- 1) As described previously, I will use a Linux system as client.
      Does someone know if a smartphone is already embedding the "Easy
Connect" function?
      I've read Android 10 provides some APIs. Does it mean I will
have to create an application?
      Does someone already used successfully a device?

- 2) On my Raspberry, since I enabled the DPP in the WPA_KEY_MGMT, I
cannot start anymore hostapd and got the following error:

Mar 27 09:10:54 ubuntu hostapd[2432]: wlan0: interface state
UNINITIALIZED->COUNTRY_UPDATE
Mar 27 09:10:54 ubuntu hostapd[2432]: wlan0: Could not connect to kernel driver
Mar 27 09:10:54 ubuntu kernel: ieee80211 phy0: brcmf_configure_wpaie: ivalid OUI
Mar 27 09:10:54 ubuntu hostapd[2432]: Failed to set beacon parameters
Mar 27 09:10:54 ubuntu hostapd[2432]: wlan0: Could not connect to kernel driver
Mar 27 09:10:54 ubuntu hostapd[2432]: Interface initialization failed
Mar 27 09:10:54 ubuntu hostapd[2432]: wlan0: interface state
COUNTRY_UPDATE->DISABLED
Mar 27 09:10:54 ubuntu hostapd[2432]: wlan0: AP-DISABLED
Mar 27 09:10:54 ubuntu hostapd[2432]: wlan0: Unable to setup interface.
Mar 27 09:10:54 ubuntu hostapd[2432]: wlan0: interface state DISABLED->DISABLED
Mar 27 09:10:54 ubuntu hostapd[2432]: wlan0: AP-DISABLED
Mar 27 09:10:54 ubuntu hostapd[2432]: wlan0: CTRL-EVENT-TERMINATING
Mar 27 09:10:54 ubuntu hostapd[2432]: hostapd_free_hapd_data:
Interface wlan0 wasn't started
Mar 27 09:10:54 ubuntu hostapd[2432]: nl80211: deinit ifname=wlan0
disabled_11b_rates=0
Mar 27 09:10:54 ubuntu systemd[1]: hostapd.service: Control process
exited, code=exited, status=1/FAILURE

Can someone give me some details about the error (Invalid OUI) and
provide sone details how to resolve it? As you can see in the
following hostapd.conf, I would like to continue to also use WPA-PSK
in parallel to DPP. FYI, I got also the same error if only DPP is
present.

/etc/hostapd/hostapd.conf:
interface=wlan0
driver=nl80211
ctrl_interface_group=0
ctrl_interface=/var/run/hostapd

##### SSID
ssid=SpeedPort PI
channel=6
country_code=FR
ignore_broadcast_ssid=0

##### IEEE 802.11n Configuration
ieee80211n=1
hw_mode=g
wmm_enabled=1

##### IEEE 802.11w Configuration
ieee80211w=1

##### AP Authentication
auth_algs=1
wpa=2
wpa_passphrase=0123456789
#wpa_key_mgmt=WPA-PSK
wpa_key_mgmt=WPA-PSK DPP
wpa_pairwise=CCMP
rsn_pairwise=CCMP

Thanks a lot for your help,
Best Regards,