I need an app that can schedule whatsapp messages to all my whatsapp contacts. I will put both mobile data and wifi off during the scheduling and put it back on when it is finished so it can start sending the messages. Sim blocking is not an issue. I must be able to see the scheduled messages when I open whats [url removed, login to view] content of messages to be scheduled can include text, images, sound and video. If whatsapp blocks the sending sim, I will verify another number to [url removed, login to view] must be able to schedule for over ten thousand contacts at a time. The contacts will be in whatsapp already. I will have to try a demo version that can schedule about a thousand contacts before payment will be made. My device is a Samsung galaxy tab 3.