Hi Kaka Nayeem,

Please view the discussion here, Update Sets or Applications?

Personally I would tell, for isolation and security, you can use scoped apps. Added advantage are,

• Dependencies - if you build a custom app that makes use of CMDB (or Incident or another custom app), that dependency is captured and you can see what other resources an app makes use of before you even install it.
• Isolation - when you are building a scoped app and try to make changes to a resource in another scope (including Global), the platform will flag that for you and you can respond accordingly.   How many times have you been working on one thing, forgotten to change update sets and accidentally included a change for something else?   Simply not a problem in a scoped app.
• Interfaces - You can now make a Script Include private to your application so only your app can access it.   Same thing with tables, what previously required a whole mess of roles & ACLs can now be achieved with a couple checkboxes.   You can make a table entirely private to your application or expose it for read-only while forcing updates to occur through a Script Include (think conference room scheduling, reading the rooms and their schedule by other apps isn't a problem, but to schedule a room, you can actually require a call to your Script Include which could check availability, priority and all sorts of other things before actually inserting the row)

Update sets can be preferred for any minor customization changes.

Thank you,

Vinitha.K

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