Backup Mobile Phone SMS Forwarding Solution

1. Introduction#

Due to the increasing number of accounts that do not support registration with domestic mobile phones and GV, I recently bought a free SIM card from abroad to use. However, when there are multiple cards, problems arise. I don't like to carry two phones when I go out, and they are about to fall out of my pocket. So I had to find a solution to only bring one phone when I go out.

2. Forwarding Solutions for Android Backup Phones#

1. SmsForwarder + Telegram Bot#

SmsForwarder

SmsForwarder is an open-source library on Github that supports monitoring SMS, incoming calls, and app notifications on Android phones and forwarding them. It also includes functions such as remotely controlling sending messages, checking messages, checking calls, checking call logs, and checking battery levels.

Here is a simple setup process based on the official documentation. If you don't want to use Telegram Bot, you can refer to the documentation for self-configuration.

General Settings

Open the overall switch of the forwarding function as needed, and the necessary permission authorization will pop up. If the authorization is not normal, please manually set the permissions in the "Settings" of the phone (grant all permissions without hesitation).
It is recommended to enable the first three settings for keeping alive.
In the personalized settings, click refresh to automatically obtain the SIM card slot remarks. If the SIM card slot in the forwarded message is matched incorrectly, set the SIM card slot primary key according to the SubId.
If the device is in an unstable network environment, please set the retry mechanism for the request.

Sending Channel

I use Telegram as the forwarding tool, but you can also use SMS or email, etc.

Apply for a Telegram Bot

Chat with @BotFather and apply for a Bot
After sending /newbot, enter the nickname of the bot
Then enter the username of the bot
Get the apiToken and enter the username of the bot mentioned above
Obtain the apiToken, the format is as follows: 1234567890:ABCDEFGHIJKLMNOPQRSTUVWXYZ
Copy the apiToken to the "ApiToken of Setting Telegram Bot" field
Chat with your own bot and say something random; or create a group, add the bot to the group, and say something random in the group.
Then open this link https://api.telegram.org/bot<apiToken>/getUpdates (PS. Note that <apiToken> should be replaced with your own)
ChatID value is in result->message->chat->id (personal is pure numbers; group is negative numbers, type: group;)
Get your own (or group) ChatID and paste it into the "ChatId of the person to be notified" field
Click the "Test" button to verify

Call Forwarding Rules

Select the Telegram Bot that was just added as the sending channel
Execution logic -> Stop when successful
Matching fields -> All
Enable this forwarding rule

You can then send a message to test it. If there are any issues, please refer to the documentation or search on Google.

2. Tasker + Telegram Bot#

Note: Tasker is a paid app.

Apply for a Telegram Bot

Chat with @BotFather and apply for a Bot
After sending /newbot, enter the nickname of the bot
Then enter the username of the bot
Get the apiToken and enter the username of the bot mentioned above
Obtain the apiToken, the format is as follows: 1234567890:ABCDEFGHIJKLMNOPQRSTUVWXYZ
Copy the apiToken to the "ApiToken of Setting Telegram Bot" field
Chat with your own bot and say something random; or create a group, add the bot to the group, and say something random in the group.
Then open this link https://api.telegram.org/bot<apiToken>/getUpdates (PS. Note that <apiToken> should be replaced with your own)
ChatID value is in result->message->chat->id (personal is pure numbers; group is negative numbers, type: group;)
Get your own (or group) ChatID and paste it into the "ChatId of the person to be notified" field
Click the "Test" button to verify

Create a Task

Add an HTTP Request action:

Select Method as POST
Fill in the URL field with: https://api.telegram.org/bot<YOUR_TOKEN>/sendMessage
Fill in the Headers field with: Content-Type/json (you can click the magnifying glass to select quickly)
Fill in the Body with the following content (remember to replace chat_id with your own uid):

{
    "chat_id": <YOUR_CHAT_ID>,
    "parse_mode": "HTML",
    "text": "<b>%SMSRF(%SMSRN)</b> \n\n%SMSRB\n\n Time: %SMSRD"
}

Several Tasker built-in variables are used here:

%SMSRF: sender address
%SMSRN: sender name in the contacts or number
%SMSRB: body (SMS content)
%MMSRS: subject (usually only for MMS)
%SMSRD: receive date
%SMSRT: receive time

Create a Profile to call Tasker

Switch to the PROFILES tab in Tasker, add an Event type Profile: Phone > Received Text, and configure whether to filter types, senders, and content according to your needs.

After creating, select the Task you just created to link it.

3. Forwarding Solutions for iPhone Backup Phones#

By default, iPhone applications do not have permission to read message content, and the Shortcuts automation requires specifying keywords or contacts. I haven't found a way to forward messages to Android yet.

1. Forwarding to iPhone#

Launch Settings on iPhone
Go to Messages
Toggle iMessage
Find and tap on Text Message Forwarding
Find the iOS device you want to receive and send messages (only devices with the same Apple ID will be displayed)
A verification code will be sent to the requested device

Since I don't have two iPhones to test, some experts have reported that there may be synchronization issues when using different Wi-Fi networks, so it is recommended to use Android as a backup phone.