try:
RewriteRule ^/apple(.*)?$ /folder1$1 [NC]
Where the folder you want to appear in the url is in the first part of the statement - this is what it will match against and the second part 'rewrites' it to your existing folder. the [NC] flag means that it will ignore case differences eg Apple/ will still forward.
See here for a tutorial: http://www.sitepoint.com/article/guide-url-rewriting/
There is also a nice test utility for windows you can download from here: http://www.helicontech.com/download/rxtest.zip Just to note for the tester you need to leave out the domain name - so the test would be against /folder1/login.php
to redirect from /folder1 to /apple try this:
RewriteRule ^/folder1(.*)?$ /apple$1 [R]
to redirect and then rewrite just combine the above in the htaccess file:
RewriteRule ^/folder1(.*)?$ /apple$1 [R]
RewriteRule ^/apple(.*)?$ /folder1$1 [NC]