There are many programs which work by taking a initial snapshot of the system and comparing with a final one make portable apps.
However these apps themselves require an installation.
I would be glad if someone makes a "app maker"
Cameyo and VM Ware Thin App are two such softwares and i know they are not opensource but someone could try making them and it will be a landmark success if someone does because then all other apps can be made in a jiffy.
I know the programs will need admin rights but then that's ok as long no permanent changes are made.
"I know the programs will need admin rights" It is not a prerequisite for the installation of all programs. Modern virtualization technologies allow to bypass this condition.
On boxedapp page U can read about the portable version of application
"Why and when is it useful?
When an application must run properly even if it doesn't have the right to write to the system registry and to the file system.
When an application uses DLL and files, which are to be kept secure, and because of that you can't save them to disk.
When an application needs ActiveX but doesn't have an installer because it must run instantly, without the installation (for example, when it's a portable application that runs from a flash card)."
As you can see portable applications have some advantages
Most (if not all) of the programs in that category have issues that stop us from doing it.
1) The app itself costs a massive amount of money to legally use, therefore it is illegal to make a portable version without charging for it and without dealing with the developer of the app.
2) Apps made portable with those types of programs often cannot be legally distributed due to licensing issues with the portablizing app or the app being made portable.
3) These programs cannot guarantee that a program you make portable with them will actually work in a fully portable manner. They are often hit & miss with including app dependencies properly, and will sometimes break the app more than it will make it portable.
I want to add - a portable version of the program is not always an exact copy of the original version. But it has all the features of the original version.
I've been wanting to ask - what applications can not be portable?
I do not mean the legal side of the issue.
If you are specifically talking about apps made portable with technology such as Cameyo, ThinApp etc. then there is no hard and fast rule as to what can and cannot be made (completely) portable. Generally the more dependencies the app requires that aren't contained in its own folder then the more likely something will be missed or broken in the packaging process.
If you are talking about restrictions that mean an app can't be made portable the PortableApps.com way, I commented on another thread with pretty much exactly the answer to that just last week so you can check that comment out here if you'd like.
Thank you very much!!
I was misled by some of the comments
I thought what kind of applications can not have a portable version? Thanks for the explanation!
I was once in some communication with VMware/Thinapp representatives, who did a big project in trying to run complete network of one county administration as virtual system with portabilized apps.
Sure they did not succeed to make all 100% work.
I asked them if they are able to make portable version of this and that, but also those guys did not say that they can do all programs.
Their answer was simple : bring the program to us and we will try. It may work or not. And they use this Thinapp system to portabilize single programs and have lot of experience with all their virtual systems etc.
Yes, but these programs are rare
I had contact with the Vmware people some time ago, they said that some 20-30% of the software which the end users wanted to use, they have given up, as full compatibility could not be reached.
Examples given were number of CAD software , geographic information systems programs and some fast database search programs.
Also one of the CAD software I was using that time was described as not possible to be portabilized.
Those people were engineers and salesman from VMware, I assume simply if all would be that simple, they would not be so careful in their saying.