How to Experiment With JavaScript on Your iPad

Love it or hate it, JavaScript is a language every modern-day programmer should be familiar with. While I've previously discussed ways to learn JavaScript interactively, sometimes a great book is essential for getting a firm grounding in the subtleties of the language. But reading isn't enough: You have to experiment, too.

If you're sitting in front of your computer and learning, a cutting-edge JavaScript interpreter is always just a click away, tucked into your browser's Developer Tools. But let's say you're lying in bed late at night with your Kindle Paperwhite, reading an in-depth overview of some intricate language features. You can't start tapping away at your laptop, even if it's next to you. The solution is to pull out your iPad and try out some code using the free and excellent Jasic app.

Here's a chirpy little video showing what Jasic dreams of being:

https://www.anrdoezrs.net/links/7251228/type/dlg/sid/UUmuoUeUpU56389/https://vimeo.com/66526721

In a nutshell, Jasic app wants to be a full-fledged development environment, letting you create full apps using nothing but your iPad (and, mercifully enough, a hardware keyboard). You can then export your JavaScript project to Xcode and continue working on it on your PC.

That's never going to happen, at least not for the majority of users. Jasic is nice, but coding complex applications on an iPad is simply not a practical proposition. But Jasic is still an app you need to have on your iPad if you're learning JavaScript.

Jasic may not live up to its own dreams, but it is a beautifully capable JavaScript scratchpad with lots of IDE convenience features.

Under the hood, Jasic offers a thoroughly modern interpreter that's almost compliant to ECMAScript 5.1. Some advanced language features are not supported, most notably

eval()

. In practice, it can be used to play with and understand nearly any JavaScript feature and syntax quirk.

In terms of the interface, you get a console so you can

console.log()

to your heart's content. There is also syntax highlighting, as well as auto completion -- incredibly useful when tap-tap-tapping on a touchscreen keyboard.

Speaking of the keyboard, Jasic's keyboard includes an additional row of keys, giving you access to all of those essential characters:

Note the two Alt keys: That single row actually packs 27 different keys, since each key has three separate functions. The black state is the default, while the blue Alt key activates the blue state, and the red one switches on the red state. The ever-present semicolon is now just a single tap away, as is the equal sign. You can easily quote strings, create all three types of braces, and navigate your code with the arrow keys. It rocks.

You can also save your files and get back to them later.

Jasic doesn't have any adverts or nagging reminders to upgrade - it's entirely free, and it lets you work in peace. If you do want some extra oomph, you can opt to buy a debugger for $2, an OAuth library, an SQLite library, and some other relevant add-ons. The complete bundle of optional extras will set you back $8, but again, if you're just learning JavaScript, it is entirely unnecessary (except for that debugger perhaps).

I can't overemphasize the importance of trying out code snippets while reading a JavaScript book, and Jasic lets you do this on the go (or in your bed). I find that tapping out the code (rather than copy/pasting) helps me understand JavaScript's little syntax quirks better, too. A wonderful tool for learning -- highly recommended.

Download: Jasic for iPad (free) [No Longer Available]