EZ FLASH IV

The current kernels for the EZ4 actually can automatically patch things internally, which is to say you drag and drop ROMs you want onto the card and they just work. ( https://www.ezflash.cn/download/ , initial release of the onboard patcher https://gbatemp.net/threads/ez-flash-iv-2-0-kernel-release-no-more-patching.473577/ )
They also support SDHC class devices (4 gigs and up to 32 gigs, be careful as a lot of shops will only stock 64 gigs and up) as opposed to the older SD class (up to 2 gigs). You will need a SD class device to update it if it is on that old a kernel, after that you will probably need to change to a SDHC class (still still get their SD class cards to work if formatted properly but others have troubles, we never never managed to figure out how though)..

I have never liked those micro to mini adapters as they are frequently the cause of contact issues and with it any number of issues that vanished the instant. Sadly miniSD form factor SDHC is not something that exists as far as I am aware so back to finding an adapter and hoping it works. I don't know why they are so bad -- when it comes to microSD to full blown SD then I have had dozens of adapters go through endless abuse and come out just fine but it is what it is.


If you are using older kernels.
GBATA's SRAM patch (and clock patch for those things that want it, though there are alternatives http://gbatemp.net/threads/buying-a-gba-flash-cart-in-2013.341203/page-18#post-4756995 ) might have been used to allow it to save.
The EZ4client program functions much the same way. It patches GBA (and DS) games to work with the EZ4's SRAM memory as opposed to what it expects normally. Originally it did have batch support but that broke somewhere along the line.
There are a few EZ4client alternatives
https://github.com/HiddenRambler/EZ4Patcher being one of them.
That said with the modern kernels it is unnecessary.