I hope I get some replies, as searching on net it seems a lot of users encounter the same problem. Suggestions such as " make sure you got the + sign in front of numbers", or having them stored in your favourites or even store numbers on phone rather than SIM, do not resolve the issue. WhatsApp's FAQs do not provide any tips either..wonder if it is a glitch they have...
Whatsapp will pull the contacts from your phone contact list. Only people who have whatsapp will appear in the whatsapp contact list.
If you just added a contact, you'll want to hit menu>update contact list.
There are some work around to get whatsapp on your tablet, but you need some knowledge over rooting and flashing process.
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