My son is using the Omnipod and although you don't need to take the controller ( PDM) out with you it is advisable as the device is also the blood glucose monitor. There is no where on the pod itself to give a bolus so you will need the device when you are eating, also should you wish to suspend the background insulin. You could wear a pump belt to carry the device rather than having it in a pocket or bag.
We don't find it to be a problem as we used to carry a blood testing monitor and insulin pen. Although the remote is on the large side it along with the pod itself has been redesigned and will be available at the end of the year. We have been told that we will automatically be sent the new PDM along with the new pods and don't have to re- apply for funding.
Hope this helps.