https://www.romhacking.net/utilities/13/ works for me.
That said I will note some are moving away from IPS, especially for the GBA.
Its three main flaws are
1) It has a 16 megabyte size limit. Most are 16 or less but the GBA can go to 32 without having to get exotic, and some ROM hackers go there should they need the extra space as it is trivial to do.
2) It has no verification. No so bad on the GBA as there are not usually random headers added (see the SNES) but if people do try to feed things other regions, other versions, existing hacks and the like it won't care or even know the care. For some things this is an advantage, and in this case you appear to want to stack hacks*
3) It can't relocate data. Not as bad on the GBA as things are rarely relocated, though pokemon hacks can be the exception (enough is known about the games that some tools will repoint everything to make some space for something else). For the DS on up then repointing is standard (ndstool and co don't exactly put things back in the same order and location), though you can still insert things manually (mind you DS ROMs being over 16 megs is also nothing major).
*you might want to get a bunch of popular hacks and see what extra space they might use and work your translation around it. Hopefully you can just feed advance text with the hack patched ROM and it will autodetect but it has been years since I looked at advance text.
Addition fun comes from the thousand different implementations, some of which are bad, and mods to the format for various things. At the same time I will recognise some flash cart software and emulators do support it.
What people replace IPS with varies. UPS was popular with some on the GBA but I am not such a fan. Xdelta was popular on the DS and works well, also has none of the problems listed above. BSdiff is also good stuff, also used in several hacks over the years and outside ROM hacking is the traditional rival to xdelta.
There are a thousand other patch formats (PPF, BPS, plain deltas/diffs,
http://www.romhacking.net/?page=uti...level=&perpage=200&title=&desc=&utilsearch=Go lists several more) but I would think long and hard before using them.
