Why should I use an Online Job Application Form?
To put it plainly: it's an essentially improved way of dealing with all those precious souls aspiring to join your company. Yes, there's no physical aspect to it, but you can make up for that with a follow-up interview if the form answers intrigue you enough. This option is faster, easy to manage, and provides a more comfortable space for all people, as some might have a bad time and even sabotage themselves on in-real-life interviews).
Are the forms customizable?
As much as you'd like them to be. Starting from a sample as a reference point, every "Online job application form" template (or OJAFBT for a shorter but impossible to pronounce option) allows you to set the inner child free and make it look just like you imagined. Work with colors, fonts, design, questions... the form itself is going to catch people's attention more than the offer itself.
How can I use these templates?
It's simple. Embed a form onto your website or social media pages with a call to action. For example: "C'MON MAN, WE'RE HIRING!". Something like that. You could also email the form, but when it comes to reaching potential employees, the web/social media thingy might be a better suit for your needs.