How to stop Ingress from vibrating the phone

Zoomed in you can see that a shield is there or not by it's glowing sphere animation around the column of the portal. I believe the color is more intense for a rarer shield. I am unable however to count the number of shields.

If you don't need them, give it to your faction L1 players, so that they can deploy them and therefore level up.

L1 resonators are perfect to booby trap the portal, as it will get destroyed very fast especially if put close to the strongest resonator, the owner of the resonator will get notified once it is destroyed and can counter attack - recharge the portal remotely.