At this time, generally the Smartphone has 2 SIM Card (Subscriber Identity Module) slots. so we can use two numbers on one handphone/smartphone. Also for the Apps like WhatsApp, we can use two WhatsApp number on one smartphone. Now, smartphone has also 'Dual Apps' capability so one app can be used for two accounts at the same time.
To know whether your Android smartphone has Dual Apps capability, go to Settings, Apps. you will see 'Dual Apps' on there if your smartphone has, and lists of Apps those support using dual Apps.
How to set two WhatsApp numbers:
To set the second WhatsApp of course you have to have active SIM card on the the second SIM card slot.
1. Go to 'Settings' --> 'Apps' --> 'Dual Apps'
2. Look for 'WhatsApp' . then turn it on, (become blue from gray)
3. In the home screen then you will see the new WhatsApp icon with small yellow circle on it.
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4. Run the new WhatsApp icon, then follow the instruction same as usually you install the whatsApp in generally.
