I wanted a flash drive that would allow me to easily move photos between my new iPad and my computer. As for the amount of storage you can get on a flash drive, it generally seems cheaper to spend $15-20 for one rather than $100 to add more storage to the tablet itself. I love how many different I/O options there are for this drive (a micro USB adapter was included with my order).
Samsung BAR Plus 128GB USB 3.1 Flash Drive - 400MB/s - Champagne Silver (MUF-128BE3/AM)
65 Review
Kingston DataTraveler flash drive 100 G3 256 GB, 1 pc. black
74 Review
Compact and Convenient: SanDisk Cruzer Fit USB 32GB Flash Drive (SDCZ33-032G-A11)
66 Review
Titan Gray Samsung BAR Plus 256GB USB 3.1 Flash Drive (MUF-256BE4/AM) with Up to 400MB/s Transfer Speed
69 Review
18 TB External HDD Western Digital WD Elements Desktop, USB 3.0, black
95 Review
8TB Seagate Backup Plus Hub Desktop Hard Drive with Data Recovery Services
56 Review
π Seagate Expansion 3TB Portable USB 3.0 External Hard Drive (STEA3000400) in Black
60 Review
2 TB External HDD ADATA DashDrive Durable HD650, USB 3.2 Gen 1, Blue
55 Review