According to Tester's Point of view------
1) Web Base Application (WBA)is a 3 tier 
application ;Browser,Back end and Server.
      Client server Application(CSA) is a 2 tier 
Application ;Front End ,Back end .
2) In the WBA tester test for the Script error like java 
script error VB script error etc, that shown at the page.
      In the CSA tester does not test for any script error.
3) Because in the WBA once changes perform reflect at every 
machine so tester has less work for test.
      Whereas in the CSA every time application need to be 
instal hence ,it maybe possible that some machine has some 
problem for that Hardware testing as well as software 
testing is needed.

actually in web based testing we main concentrate on 
browser compatability .why bec in IE it display gui objects 
correctly but in the Netscape it will change the position 
of gui objects should be changed.
after words we will check broken links,image links,home 
page from every page,securities,cookies,donot divide the 
pages into more frames,colors,fonts,images.


In the client server application we will check response 
time,normal functioanlity,server load,deadlock.

Hai
As per my knowledge
Web Based App means:
1.The web app can be developed by using any kind of tech 
like "java,.Net,etc.
2.It's a 3 tier arch.i.e
a.Business tier
b.Presentation tier(HTML,DHTML,SERVLETS)
c.Data tier(Oracle,SQL Server)
3.If any change occure in app that will effect only sever 
side.means here no need to bother about the client means 
client is thin client means  browser.
any change occure in app the entire app is installed in 
sever only becoz in this the core app will reside at server 
side only.

Client server App:
1It's a 2 tier arch.
b.Presentation tier(HTML,DHTML,SERVLETS)
c.Data tier(Oracle,SQL Server)

2.In client server app ,the app will reside in client side 
only .means if any change will occure in app that will 
effect the client.

Difference between web based application and client server 
applications are as follows:

1)Client server applcation directly we can launch
where as for launching the web based applcations we need 
start database server,web server and by using internet 
explorer (URL) we can launch web based application

2)Client server applications are menu driven where as web 
based applications are liks driven to get the next page.

3)Client server application will contain less content, and 
with less images
when compared to web based applications
web applications will contain more content with more images