Fleio is described as 'billing solution and self-service control panel for OpenStack that enables a public cloud startup to launch its OpenStack services offering in a matter of days' and is a Cloud Computing Service in the Business & Commerce category. There are more than 10 alternatives to Fleio for a variety of platforms, including Linux, Online / Web-based, Self-Hosted solutions, Windows and Mac. Most alternatives are Cloud Computing and Cloud Hosting Services. The best alternative is Proxmox Virtual Environment, which is both free and Open Source. Other great apps like Fleio are OpenStack (Free, Open Source), VMmanager (Paid), Xen Orchestra (Freemium, Open Source) and CloudStack (Free, Open Source).
XO is a web UI providing a simple and nice web interface to manage XCP-ng and Citrix Hypervisor (formerly (XenServer) infrastructure (VM, servers, pools, etc.). It's also a fully feature backup solution for those platforms.
Apache's CloudStack is a Project backed by Citrix and designed to be a direct competitor to OpenStack. It is designed to deploy and manage large networks of virtual machines, as a highly available, highly scalable Infrastructure as a Service (IaaS) cloud computing platform.
VirtEngine is an Open Source Cloud Management platform that integrates with OpenNebula (Compute), Docker (Containers), Bitnami (Applications), and Ceph (Storage), WHMCS (Billing: Commercial) in a simple and powerful User Interface for the user.
WebVirtMgr is a libvirt-based Web interface for managing virtual machines. It allows you to create and configure new domains, and adjust a domain's resource allocation. A VNC viewer over a SSH tunnel presents a full graphical console to the guest domain.