Is Bubble free or paid?

Could you please clarify for me if the Bubble service is offered free of charge or if it requires a payment? I'm interested in understanding the financial implications of using Bubble, as it could affect my budgeting decisions. Additionally, if it's paid, could you provide information on the pricing models available and any potential discounts or promotions that might be offered? This information would greatly assist me in making an informed decision about whether or not to utilize Bubble for my needs. Thank you for your time and assistance in this matter.