Not all tablets have a SD card reader built-in. That means you are going to have to pick up an adapter to read SD cards on them. Here are 5 SD card reader adapters for iPad and Android tablets that let you do just that:
Samsung USB & SD Connection Kit: designed for the Samsung Galaxy Tab 10.1 & 8.9. It is what you need to move files from an SD or micro SD card to your tablet’s internal storage.
Lightning to SD Card Camera Reader: a SD card camera reader for your iPad 4 and iPad mini (for Lightning devices).
iPad Camera Connection Kit: this is the adapter you need to attach a SD card to your older iPads.
EZOPower Micro-USB 2in1 for Galaxy S3: a SD card adapter for the Samsung Galaxy S3. It handles SD, microSD, MS & M2 cards.
ASUS External Card Reader for Transformer: made for ASUS Transformer Android tablets. Works with TF101, TF201, TF300, and TF700 ASUS tablets. It provides support for SD, SDHC, MicroSD, and MMC cards.
There are other generic SD card readers you can use to connect SD cards to your tablet. The good news is you won’t have to spend a fortune to get one.