I would like to come back to Bulb but am afraid I would lose my Smart Meter in home display functions which I find really useful. Does anyone know if the EDF Smart Meter works with Bulb. I am loath to change if they are not compatible.
If it is SMETS1 then no.
I suppose it depends on what is more important to you the functions ot the savings £s 
Bulb have started installing the better version so it may just be a short term (ish) inconvenience.
How do I tell if it is SMETS1 or 2?
You google it Unless someone else knows better. In other words I dont really know.
I don't believe there's anything actually on the meter that says 'I'm a SMETS2', just been looking through my catalogue of meter pictures and none of them do anyway.
There is, however, one big giveaway difference between SMETS1 and SMETS2 and it's the communications hub. Generally, in my experience, the comms hub for SMETS1 is either part of the meter itself (and therefore not visible as a separate device) or, in the case of L&G meters, has a smaller, thinner device somewhere nearby (probably from Trilliant) which provides the remote communications.
In SMETS2, the communications hubs all look similar in that they’re big, square boxes that should sit on top of the electricity meter and will have a number of barcodes on them. Another key giveaway is that the meter will have a Meter Serial Number (which everyone is used to and knows and loves) but it will also have a ‘GUID’ or a Device ID which looks like this: AA-BB-CC-DD-EE-FF-00-GG-ZZ.
The comms hubs also have several LED lights on them in a row which will indicate whether it’s connected to WAN, gas, Mesh network and HAN. SMETS2 comms hubs will also have a ‘SKU’ label on them - SKU1, SKU2 (but that’s only for the Central and South region).
I have an EDF SMETS1 smart meter. Whilst it doesn’t send meter readings to Bulb and I now do that manually, the IHD continues to link to the meter and display all the same usage data in kWh and the correct meter reading so that I don’t have to leave my flat to get to the actual meter. Obviously the unit prices are wrong but they never updated when I was with EDF anyway.