Finally success to make it done. Attach my settings for reference:

1. If plug to LAN, it will create two IP for LAN and Home Wifi
2. If unplug LAN, it will connect to Home Wifi. But it takes around 30 seconds delay to ping local LAN during boot-up time
3. If on the street, it will connect to the 4G router

After fresh Raspyfi 1.0 install:

sudo apt-get update

1. sudo nano /etc/network/interfaces
auto lo
iface lo inet loopback
auto eth0
iface eth0 inet dhcp
allow-hotplug wlan0
auto wlan0
iface wlan0 inet manual
wpa-roam /etc/wpa_supplicant/wpa_supplicant.conf
iface default inet dhcp

2. sudo nano /etc/wpa_supplicant/wpa_supplicant.conf
ctrl_interface=DIR=/var/run/wpa_supplicant GROUP=netdev
update_config=1

network={
ssid="AirExtreme"
psk="99999999"
proto=RSN
key_mgmt=WPA-PSK
pairwise=CCMP
auth_alg=OPEN
}

network={
ssid="4GLTE"
psk="99999999"
proto=RSN
key_mgmt=WPA-PSK
pairwise=CCMP
auth_alg=OPEN
}

I'd like to set 3 network options for the Raspyfi
In priority:
1. Local LAN
2. Home Router (Apple Airport Extreme)
3. 4G LTE Router (Huawei E5776).

I followed many posts on the web but still not success.
I can only connect either Apple Airport Extreme or 4G LTE Router by comment one of it in the config
I cannot connect to local LAN by this settings up-to-now...

My /etc/network/interfaces:

auto lo
iface lo inet loopback
iface eth0 inet dhcp
allow-hotplug wlan0
auto wlan0
iface wlan0 inet dhcp
# wpa-ssid "AirExtreme"
# wpa-psk 99999999
wpa-ssid "4GLTE"
wpa-psk 99999999
#pre-up wpa_supplicant -Dwext -i wlan0 -c /etc/wpa_supplicant/wpa_supplicant.conf -B

My wpa_supplicant.conf:

update_config=1

#network={
#ssid="YOURSSID"
#psk="YOURPASSWORD"

# Protocol type can be: RSN (for WP2) and WPA (for WPA1)
#proto=WPA

# Key management type can be: WPA-PSK or WPA-EAP (Pre-Shared or Enterprise)
#key_mgmt=WPA-PSK

# Pairwise can be CCMP or TKIP (for WPA2 or WPA1)
#pairwise=TKIP

#Authorization option should be OPEN for both WPA1/WPA2 (in less commonly used are SHARED and LEAP)
#auth_alg=OPEN
#}

network={
ssid="AirExtreme"
proto=WPA
key_mgmt=WPA-PSK
pairwise=TKIP
psk=99999999
auth_alg=OPEN
priority=1
}

network={
ssid="4GLTE"
proto=WPA
key_mgmt=WPA-PSK
pairwise=TKIP
psk=99999999
auth_alg=OPEN
priority=2
}

Am I doing something wrong? Many thanks.