My carrier is Telcel (Mexico) Its prepaid that I haven't paid for since using the VPN, as it allows me to have free internet, and this method allows me to share it with all my devices, I've used 30GB of data in 2 weeks.
Disclaimer: not responsible for your device in anyway, even though this should not harm anything
STEP 1: You need a rooted device
STEP 2: Make sure you have a VPN app, like OpenVPN or DroidVPN ( I use DroidVPN and its the best)
STEP 3: Download Terminal Emulator
STEP 4: Activate your hotspot and connect to your VPN
STEP 5: launch Terminal emulator and on the first line type "su" (without the quotes) and press enter
STEP 6: Copy and paste this to the Terminal Emulator, MAKE SURE TO PASTE TO A NEW FOLDER USING ROOT BROWSER FIRST, AND COPY TO T.E. IN THE EXACT FORMAT AS SHOWN
iptables -t filter -F FORWARD iptables -t nat -F POSTROUTING iptables -t filter -I FORWARD -j ACCEPT iptables -t nat -I POSTROUTING -j MASQUERADE ip rule add from 192.168.43.0/24 lookup 61 ip route add default dev tun0 scope link table 61 ip route add 192.168.43.0/24 dev wlan0 scope link table 61 ip route add broadcast 255.255.255.255 dev wlan0 scope link table 61
Also be sure to make a folder with Root Browser and paste the code there, as this resets after re-boot.
Please comment if this worked for you, it worked on my LG G3 on android 4.4.2