My iPad has not updated since ios10.3.3. How do I update to latest iOS?

You don't.

Sorry.

If your iPad has been stuck on iOS 10.3.3 for the past few years, with no upgrades/updates forthcoming, then you own a 2012, iPad 4th generation.

A 4th gen iPad cannot be upgraded beyond iOS 10.3.3/10.3.4 for WiFi AND cellular data models.

A 4th gen iPad is a NEARLY 8-year old device, now!

These older iPad models are too old, now, too underpowered and completely incompatible with any of the current and future versions of iOS/iPadOS.

It is what it is, today, in the year 2020!

Apple supports new iPad models for up to 5-6 years with third party app developers supporting these iPads for another, additional 2-3 years after!

So, that is a total of between 7-9 years of iPad/iOS support!

ALL older iPad models, like the iPad 2, 3, 4 and 1st gen iPad Mini have, finally, reached this support limit!

If you need an iPad that can run the latest and greatest versions of iOS, as well as, the most current apps available, then, you need to purchase a new iPad from Apple or a discounted, refurbished iPad from Apple’s Refurbished & Clearance section of Apple’s Website or a new or refurbished iPad from an Apple authorised, third party retail or online reseller OR other trusted sources for new or used Apple products.

These old iPad 2, 3, 4 and 1st gen iPad Mini models are, virtually, 8 and 9-years old, now.

The amount of older, compatible, available apps for these old iPad models has dwindled significantly since the beginning of 2020!

Getting older versions of apps for these old iPad models, initially from Apple’s iOS App Store is getting very difficult and very problematic and this issue is getting, painfully, much worse, now, in 2020!

As of the beginning of 2019, many, MANY third party app developers are all more quickly and completely permanently dropping older app support for all old 7, 8 and 9-year iPads that are running 2-3 year old and earlier iOS versions ( iOS 10 and earlier ).

Third party app developers are removing all of their older, legacy versions of their apps from Apple's App Store servers, now.

Third party app developers no longer want to support these 8 and 9-year old or older iOS devices, any longer!

Older versions of apps are, soon, going to be gone for good, now!

These old iPads are now reaching their complete end of life and support cycles.

So finding older versions apps for older iPads, while still possible, currently, will be a very tough challenge, now, in 2020.

Old iPads that can no longer be upgraded/updated will have NO MORE APPS AVAILABLE for initial download, at all, soon, from the Apple iOS App Store, for such old iOS devices in the very near future.

Older versions of apps for these older iPads will be completely gone, at some point, in the very foreseeable future.

Old 8 and 9-year old iPads will be pretty much obsolete by the end of the 2020 year!

Again, it is what it is, today, in the year 2020!

You will never get any more older versions of popular apps for these old iPads, any longer.

The apps that these old iPads already have on them, and still work, will be the apps these iPads will be stuck with!

Basically, these old iPad models are just good for FaceTime and somewhat limited Web browsing via some other, more up to date third party Web browsers and NOT using that nearly 4-year old iOS Safari Web browser.

So, this is REALLY NOW the time to seriously consider a new or discounted, refurbished iPad from Apple or other Apple authorised resellers.

A lot has happened with iPad and iOS in 7-9 years and in the past 2 to 3-1/2 years since iOS 9 and 10.

As an example and compared to that nearly 8-years old iPad 4th generation model,

The cheapest, baseline 2019, 10.2 inch screen 7th gen Apple iPads have a 1/2 inch larger retina screen, it is overall lighter, in weight, newer, more powerful and approx. 2-1/2 times faster 2.3 Ghz, A10 Fusion processor ( CPU ), AT LEAST 3-4 times the internal RAM, with the 2019, 7th gen iPad having 3 GBs of internal RAM, iPadOS 13 support, with much better and improved multitasking features and much fuller support for externally connected data drives, Apple Pencil and Apple Smart keyboard cover support and have better audio speakers and better/improved built-in cameras.

In addition, if you search online and look at various, reputable online Apple device resellers, you can usually find this 2019, 7th gen iPad at various discounts, depending on storage size and whether it is a WiFi ONLY model or a WiFi/cellular data model.

This is the harsh reality for these 8 and 9-year old, OR OLDER, iOS devices, now!

Sorry & Best of Luck to You!

If your iPad is currently running, or cannot be updated beyond iOS 10.3.3/4, then have an iPad4 - which may be confirmed from your model number (Settings > General > About).

Update support for iPad4 ended September 2017. The final iOS releases for this model were iOS 10.3.3 (WiFi Only models) and iOS 10.3.4 (WiFi & Cellular). iPad4 cannot be updated to any later major version of iOS as it lacks the minimum hardware requirements needed to run more recent versions.

Many App Developers have also dropped support for older devices and iOS versions preceding iOS11/12/13 - and have withdrawn older versions of their Apps from the Apple App Store. Withdrawal of Apps supporting older models of iPad is making their utility and usefulness significantly more limited. Once compatible versions Apps are withdrawn, you’ll not be able (re)download or (re)install them.

If Apps that you need to use now have higher minimum iOS-version requirements, your only option is to replace your iPad with newer model. Even the basic current iPad7 supports current iPadOS 13.x - and has hardware specifications that will vastly outperform your old iPad4.

I hope this information is helpful - if only in clearly stating your current options.

What do you see when you go to to Settings-General-Software Update? If it says that your software is up to date, that means you cannot update your model of iPad any further.