Hi,
The answer is straight forward.
- SAP web ide is different from hcpms and SMP 3. It is a IDE to develop apps (like eclipse)
- SMP 3 and hcpms are platforms that helps you in development of enterprise apps with all enterprise level features like offline, push notifications etc.
- SMP 3 is on premise and HCPms is in the cloud. You will get all the features in both. It's your choice which one to go with.
I would recommend you to do a basic research to get information on these.
Regards, Midhun
SAP Technology RIG