I have a couple evangelists but I'm not seeing the number of disciples or overall believers increasing on the main or the stats page

Hi, are you referring to the first evangelists? If so, they only increase disciples every few seconds – it's the last upgrade that triggers increase every second. That being said, I have got several feedback that the evangelists are underpowered, so I will definitely look into the balancing for the next update. 

Could you also tell me your device / browser?