Duplicator Pro might be a bit more popular than Jottacloud. We know about 1 link to it since March 2021 and only 1 link to Jottacloud. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.
Most photo syncing options don't generally offer E2EE though. If you're willing to forgo that feature, Jottacloud might be an option for you, which is what I personally use. Not E2EE, but good value for the amount of storage you get, based in Norway (some of the best privacy laws around), runs on renewable energy (hydro-electric I think), and their privacy policy is decent (they also have a "privacy guarantee" page). Source: over 1 year ago
2, The logical way would be to develop the site on a staging/ dev server then move it to their live site when ready. A few things, again, need to be considered, but, for a straightforward swap, you can use a plugin like Duplicator Pro to 'duplicate' your updated version and overwrite the live site when ready. Source: over 2 years ago
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