In general no, you are on a date to spend time with them, not to chat with others on the phone. If it’s important then they’ll leave a message on your voicemail. If you are really concerned about who has called you, take a quick look at your phone. If it’s important, such as regarding a family member, then pop to one side to make a quick phone call. If you’re at a restaurant have your phone on silent and pop to the toilets if you want to check any voicemails. If you’re in the middle of a date and your phone rings, your date may assume you’ve asked a friend to make an “urgent call” as an escape for you.