2018 ipad pro 256GB vs. 2020 ipad pro 128GB

I would go for the 256 GBs model for future proofing.

The amount of available, practical, usable storage is based not only on how much iOS/iPadOS takes up but on the actual size that 1.0 GB is equivalent to, which for Apple 1.0 GB ≈1.075 GBs

Also, iOS/iPadOS devices need to maintain a minimum constant of between 2-4 GBs to ensure nominal, expected performance and function of iOS/iPadOS.

Also, my “current” installation of iPadOS 13.2.3 takes up approx. 5.5 GBs of my iPad's internal storage space.

Newer version of iPadOS 13/14 maybe taking up EVEN MORE internal data storage than my version!

A 128 GBs storage iPad starts out with 119 GBs, after internal drive formatting.

Minus 5.5 GBs for iOS leaves 113.5 GBs. Minus 2-4 GBs for iOS iPadOS system reserve equals approx. between 109.5-111.5 GBs of actual, practical, usable data storage space.

256 GBs storage iPad starts out with 238.5GBs, after internal drive formatting.

Minus 5.5 GBs for iOS leaves 232 GBs. Minus 2-4 GBs for iOS iPadOS system reserve equals approx. between 228-230 GBs of actual, practical, usable data storage space.

Hope this helps in your decision-making.

Best of Luck to You!

Whilst you would be best advised to purchase as much internal storage as you can afford, allowing flexibility and space as your needs grow, another key item - that is not immediately obvious - is the RAM configuration of the iPad. Available RAM ultimately affects the overall performance of the iPad, both in terms of speed and processing power.

All of the 2018 iPads Pro, with the sole exception of the 1TB Storage model, have “only” 4GB RAM. The 2020 models all have 6GB RAM - as does the 2018 1TB model of iPad Pro.

This one specification alone is a very good reason to opt for a 2020 model in preference to the 2018. There are other enhancements, such as addition of the LiDAR sensor - but this is limited in its ultimate usefulness, whereas the RAM configuration affects everything!

Another consideration, that you might not have been thought about, is perhaps choosing a WiFi & Cellular model in preference to a WiFi Only device...

Unlike your iPhone and WiFi & Cellular models of iPad, WiFi Only iPads do not have any GPS location capability - and as such are completely reliant upon their network connection to infer an approximate location.

The WiFi & Cellular model includes GPS positioning capabilities - so the iPad can be used with [moving] Maps and other location-based services. The iPad can accurately determine its location, using GPS alone, independently of any WiFi or Cellular network connection. Accurate determination of location also affects automatic determination of time and timezone

By contrast, WiFi Only models of iPad can only estimate its location based upon lookup of the public IP address of the WiFi network with which it is being used - or though lookup of a database of surveyed WiFi neighbouring WiFi networks. Derivation of location using this technique can be reasonably accurate in urban and metropolitan environments - but is much less accurate (if it works at all) in rural and less populated areas. Without an active WiFi connection, the iPad cannot estimate its location.

Choosing the slightly more expensive WiFi & Cellular model provides flexibility in choice of network connection - and accurate determination of location - wherever you are - or whether you have any network connection. Just because you choose the Cellular-capable model does not commit you to using Cellular connections.

My personal advice, so as to preserve flexibility, would be to choose WiFi & Cellular models of iPad in preference to the WiFi Only. I am yet to see a complaint from anyone having the Cellular feature where it isn’t needed - but regularly see reports of disappointment and frustration at learning, after the fact, that the iPad lacks accurate GPS positioning capabilities.

I hope this additional information is helpful in informing your eventual choice.

Good points

I completely forgot about the 6 GBs of RAM across ALL the 2020 iPad Pro models.

Still recommend the 256 GBs of internal storage as a better base amount of internal data storage.

What do you want to do with an iPad Pro?

You’re very welcome.

RAM and GPS are not specifications/capabilities that are prominently “advertised” in the specifications - and, in the case of GPS, frequently leads to post-purchase disappointment and frustration.

Many purchasers “assume” that the iPad is similar to iPhone - in that all models of iPhone have GPS. The reality is that unlike iPad, iPhone is not available without Cellular (!) and GPS functions are integral to (but otherwise independent of) the Cellular chipset.

Only today, in this very community, I have delivered this disappointing news to a contributor. His iPad, purchased for “navigation” purposes, wasn’t working as expected whilst travelling. It was of course a WiFi Only model.