... Flash. It's a very popular development platform and it's just idiotic that Apple refuses to support it in iOS. I think I heard it was about a grudge Steve Jobs held against Adobe. I doubt there's any technical reason they couldn't support it, it runs on Mac, Windows and Android devices just fine. Let's hope they finally patch that hole in iOS 10!
Wrong answer. Flash is quite literally one of the worst things ever to happen to the web (up there with early versions of IE, and spam), and I'm glad it's mostly gone. HomeStarRunner and StrongBad were the only good uses of Flash ever. It brought unpredictable interfaces that didn't act like the rest of the standards-based Internet, most of the normal niceties one could expect from HTML didn't work (view source? Nope. Link to a particular page on a site? Nope, it's all one big Flash app. Open some link on the site in a new window/tab? Nope, it's all one big Flash app. Copy and paste some text? Nope, all one big Flash app. Hover over a link to see what action it will take? Nope, only if the designer felt like adding in some hints. Blind and have a screen-reader? Too bad, it's all one big Flash app and none of the company's web developers were blind, so they didn't bother coding specially for that. Resize the window? Not if you want to see the content, because it's all... well you get the idea.) For a while so many idiot developers had coded with the notion that IE was the only web browser, that parts of the web were effectively PC-only - "Macs and other lesser computers need not apply". There was IE for the Mac, but it lagged far behind its PC sibling, because Microsoft didn't care about the Mac. Flash was well on its way to giving Adobe similar single-company single-focus control over the web. The Mac versions never ran anywhere near as well as the PC/Windows version that the (again, idiot) web developers were using, and there was zero support for Unix/Linux/etc. It again threatened to make the web (which was literally invented not on a Windows PC but on a Next computer, running Unix and NextStep) only useable on a PC running Windows.
I don't have Flash installed on my Mac, and I don't miss it (well, the former isn't quite the whole story - there's a copy baked into Google Chrome, but I rarely fire that up). Steve Jobs had a painful history of getting held back by lack of caring on the part of other companies. Apple switched the Mac entire product line from PowerPC processors to Intel processors (a feat few other companies could have pulled off) because IBM lost interest in the PowerPC, and left Apple twisting in the wind for years with tiny speed-bump upgrades. Now we're seeing Apple designing its own CPU chips - guess why. We got stuck with antiquated Carbon apps long past when Apple had wanted everything to move to the newer Cocoa interface, because some big name companies like Adobe and Microsoft, had written all their Mac code using the Metroworks C compiler instead of Apple's own tools, and then, you guessed it, Metroworks lost interest and stopped bothering with updates for their toolchain (and there are other examples I'm forgetting at the moment). After that, Xcode got much better, and when the iPhone got 3rd-party apps, Apple forbade use of any toolchain other than Xcode for building iOS apps - that wasn't to be mean, it was because they needed everyone to be able to keep up. Apple was shown beta copies of Flash for iOS, code that Adobe wanted to force Apple to ship, so lazy web developers could keep writing Flash on the new mobile platforms just like they were doing for desktop browsers. That beta, which Adobe wanted to ship, was crap. Ran slow, hogged resources, didn't play well with others. Apple knew where they wanted to go with iOS - smaller, lighter, more power efficient, making the best use possible of the limited available resources - and Flash didn't fit in with any of that. So, Apple - Steve - refused to allow it on iOS in the form that Adobe wanted. And every user of something other than a PC running Windows cheered (or would have, if they understood), because iOS was the new hotness for a while, which meant that web developers _had_ to write proper mobile web applications to run on the new platform - and that helped Unix users, and users of any other non-mainstream OS - because those properly built websites could also run on their platforms. Apple refusing to allow Flash on iOS is the reason why I can run Safari on the Mac without Flash installed and not run into tons of websites I can't use. It's the reason HTML5 video exists. It has positive effects far beyond iOS. The tyranny of Flash was broken. Best day ever for the web.
To me, those two examples of difficulties are on the vendors, not on the iOS.
Well-designed websites have an option to access the full site and/or are fully usable on iOS and/or provide an iOS app. I don't use vendors whose websites are not iOS friendly. If they want my business, they will design for my platform of choice. I currently don't have any websites I can't use on my iPad.
That said, make sure that if you are using an ad blocker that you disable it if you're having problems with a site as that can cause site features to not display properly.
The primary problem I run into with websites on the iPad these days, are those who say, "Oh, you're on a _mobile_ device, we'll shove you into our _mobile_ website we build back in the days of the original iPhone," that are overly dumbed-down. The iPad works very well with "normal" websites (I love being able to double-tap a column of text to zoom in on it, for instance), as long as the developers steer clear of a few desktop-based assumptions, like making hovering over links a semi-required part of the interface (some pages only show some of their information that way, with no other way to access it). Many sites that send the iPad to overly dumbed-down pages will have a "request desktop site" link in the fine print at the bottom (including MacRumors, which gives the iPad the full deal, but delivers to the iPhone a page missing the "Mac" and "iOS" tabs at the top). Also, Wikipedia insists on delivering a mobile site that's pretty, but is missing things like the "Talk" tab at the top (wouldn't want to confuse those mobile users, because most of them are kids, right?). Also, in the second row of the Share Menu, there's a "Request Desktop Site" button, which works many places.
I run the
1Blocker content blocker on iOS (and the
JS Blocker extension in Safari on the Mac), but I don't run them to avoid ads (show all the ads you want, as text or images, and I'll weigh my desire to view your site against how annoying your ads are or aren't - I get that you need to pay the bills), I use these script blockers because I don't like running a ton of unvetted javascript that your website tells the browser to pull down from some third-party ad network. That's one of the most widely exploited attack vectors these days. Also, a page that drags in 30 or 40 3rd party javascript programs along with it puts an unreasonable burden on the CPU (JS Blocker puts a badge on its icon with a count of how many scripts it didn't let through - 30 is not an exaggeration; and, frankly, I don't need scripted buttons for sharing to Facebook, Twitter, Instagram, Google+, Uncle Ernie, etc. - I'm quite capable of doing those things on my own). On mobile, these scripts are chewing up my battery. On the desktop, they're spinning up my fans (did I mention I have 100 other tabs open besides your website? - web developers always assume their website is the only thing open, in the single tab of the single Safari window you're running). And on either platform, you might be bringing malware trouble whether you mean to or not. So, yeah, I block a lot of javascript when I use the web.
One last quick tip - In Safari on iOS, a long press on the "reload page" circled arrow will get you quick access to choices for "Request Desktop Site" and "Reload Without Content Blockers".