But for $5/month you can run your own "cloud": a Linode. This is a full Linux server owned by you. It runs what you want it to run, and shares its data only in the way you tell it.
Buy one via Domain Discover-- or many, many others. This piece of the Internet is by you, for you. Typically you'll have myname.com point to your Linode, and say that your Linode handles web, and email.
This will give you email (postfix), iMap access (dovecot), and a vast array of other software.
Your server can control your domain (finding hosts, getting to your email server, etc.): "bind9".
Let's Encrypt has become so popular that the Apache web server has direct support for it.
Your client can be any app with iMap support:
I patched it, added a Python module, and such. It's still open source, here. (Yes, that source code is served from a Linode I own.)
WebXMPP lets your browser be an XMPP client; it speaks web on one side to your browser, and XMPP on the other (to one or more XMPP servers). You can then access your XMPP send/receive via your web browser.
To give you on-the-fly notifications, WebXMPP can use Google Firebase Cloud Messaging--but of course that's deprecated! It also supports long polling from your browser. And, in a more experimental vein, there's a notification protocol Ping Pong. You can run this server in the background on a Linux device (I use it on my Ubuntu/Ubports phone). It talks back to the WebXMPP server, and can do blinking lights, notifications, and sounds.
WebXMPP also has support for Flowroute's SMS. You can send and receive messages (including photos) on MMS. They turn into XMPP as they head towards your own device.
For hipsters, it even has a telnet interface, so you can send/receive XMPP and SMS from a terminal.
What hardware? My current workhorse is the Nexus 5. It's not at all new hardware, but they're cheap little workhorses. If you have a little skill with fiddly disassembly tasks, you can even replace its battery. But it's really getting old; LineageOS no longer considers it a "supported" platform.
I also have a Nextbit Robin. It's a nice phone, with a great LineageOS port. I bought it when they were being sold at rock-bottom prices; those prices seem to have bounced back quite a bit. It's also widely acknowledged to have an almost impossible-to-replace battery.
Some phones which may or may not become relevant:
RSS lets you stay aware as new content pops up. A huge number of web sites are based on Wordpress, which offers RSS support. As new posts happen on a given Wordpress site, they become RSS events which your RSS Feed Reader can roll up and make viewable for you.
The "Tiny Tiny RSS" software will watch one or many RSS feeds, and provides a web interface so you can browse new articles from your web browser. (Debian "tt-rss" package).
And you can install the very nice FeedMonkey web app alongside tt-rss on your server. It's my personal favorite interface on both mobile and desktop for browsing new articles. It also provides a web interface, but its leaner and cleaner than tt-rss's, and adapts well to mobile device screen sizes.
Wordpress provides content publishing, versioning, a reasonable editor, and RSS support. Debian has a "wordpress" package.
The Linode $5/month system is a little light to run Wordpress/Apache/PHP plus MySQL. If needed, you can upgrade (on the fly) to the $10/month one, which should handle it fine.
If you can author your own web content without Wordpress, a lighter weight web server like boa (not a Debian package, you have to compile it for yourself) easily fits on a small server. Even a teeny server.
You update that page, and then the same personal home page is available on whatever device (mobile or desktop) you want to use. Creating a bookmark page is really simple; just see any tutorial on HTML with tables. When you see something new to add to your home page bookmarks, you just edit that same home page.
Web Apps are nice--especially since the content is on *your* server, not somebody else's! It's sad that "Cloud" these days means "not under your control". This is the cloud, but your own personal server being "the cloud". You can switch phones, or jump from phone to desktop, and still have the same data at your fingertips. Since the data is on your own (paid, though low cost) server, you have legal rights. For any reason, you can put your data on a new server from a new company. Both the data and the server are yours.
A shopping list app I call shopr. It's multi-user capable, with real-time sync across devices.
For taking personal notes, Cloud Notepad. Web-sync'ed notes, but uses LocalStorage on your web browser so you can see the last sync'ed content if your network is off. I often fill in notes on my desktop, then view them on the fly from my phone.
If you're somewhat technical, the Mastodon SDF server is a great place to get an account and visit.