A widget is an independent application that is embedded into a third-party website.
Ask yourself:
First of all, your Widget must highlight your expertise.
But it is also necessary that your Widget is not too specific. Indeed, it must address a wide audience.
Because, if it is only integrated in the long term on 2 to 3 sites, the operation will not be “profitable” with regard to the cost of developing this type of tool.
Armed with this reflection, make the effort to synthesize your needs in a small specification.
Having your Widget created by a developer is the right solution.
But don't neglect the graphics. This is particularly important. Indeed, with a beautiful design, your Widget has a better chance of being relayed.
The more your Widget is really interesting, the more it brings real added value, the more it will be relayed.
And, if the Internet users visiting the pages on which your Widget is integrated, appreciate it, some of them will relay it again. It is the snowball effect with so many chances of acquiring backlinks.