I find it fascinating the variety in GP surgery rules for appointments. My own is pretty good, go online and it shows the appointments for the day, can normally book same day until about 0930 - 1000 so no need to rush to the computer first thing.
Another one I know of actually closes it's appointment making functionality outside of 0800-1200, you can't even view what might be available if you try outside of that time. And you have to complete the triage form within that time frame as well, which often crashes and loses any progress.
Another is still phone only, or walk in, they are in a poorer area so I think the perception is people are less likely to use technology to book.
I do wish there was just one central system, as
@Drago says above at the 2nd one the receptionist often ends up filling the forms out themselves with the patient, it's not an efficient system.