VoIP Mobile App Development

Hello,

PLEASE READ THIS AMENDED VERSION and re-quote or confirm quote by a message.

When messaging me, please list what features can be achieved and what can't and we're good to go.

NB: I don't want an app customised from scrtatch. I just want something simple from a template like linphone or any other open source then customise to make a usable multi-tenant VoIP Softphone for IOS & Android (with windows PC as bonus) that can make/receive voip calls, divert/forward calls, etc. We can start from https://themeforest.net/item/dialer-voip-mobile-calling-apps-html-templates/21066668 or linphone or else.

I need the best quote for a very efficient VoIP Mobile App for IOS & Android users that I can monetise on Playstore, app store, etc.

Below is the list of features. Not all features can be achieved so please quote based on what you can achieve in the list below. Send me the list of what can be achieved with your skills, the plaform you will use to develop the app, and within the budget specified. As I said I want a simple voip app that works perfectly fine to call, to receive calls, to divert/forward calls, to join meetings or conference calls or host one, with voicemail,etc. The video calling part is optional but essential. The webdialling or desktop dialling part is optional so if it can be achieved fine otherwise leave it.

Telephony features* (Very important features and part of basic)
 Protocols: SIP or IAX
 Network features: TCP, UDP, TLS
 Multi-tenant VoIP Softphone (Unlimited users or tenants and installations)
 Available for Android, iOS, desktop Windows, macOS,… and maybe Linux
 Manual & auto-Provisioning
 Balance display (API)
 Rate display (API)
 Service & Product names and short descriptions
 Startup screen
 Logo and customisable logo field for business users
 Localization
 Automatic User registration/sign-up (and/or link to our website registration. Businesses to be confirmed within 24-48hours)
 Show dialled number (DNIS) / caller ID or name
 Ignore call function
 Call forwarding
 Unattended transfer
 Attended transfer
 Auto-answer
 Call recordings
 Conference host (SIP)
 Voicemail
 Number of users per tenant to be specified in back-end.
o Single user/tenant by default
o Multiple users (number to be determined in back end since it’s a cost per user per month for monthly subscriptions). E.g: £2.99/u/m. a business with 10 users will have to pay £29.90 per account per month.
o PAYG customers will pay a one-time fee for downloading e.g. £10 then use it for free (Free = means at least one top-up every trimester otherwise the app will be blocked. To re-activate, another £10 will be sought.).
o PAYG customers will top-up from £5 to £30 in increments of 5. Top-ups will only be available for 1 calendar month and will expire.
o Businesses cannot use PAYG therefore all PAYG users will be single users (and not multiple users in one account).
 API for Balance Display
 API for Rate Display
 PUSH (mobile)
 Encryption TLS/SRTP/ZRTP
 Other security features: Account password encryption, HTTPS/SFTP configuration

Codecs and wideband codecs / engine features
 Opus (Opus narrow, Opus wide, Opus super, Opus full)
 G.711 (a-law, mu-law)
 G.722
 G.726
 G.729
 Speex (Speex, Speex wide, Speex Ultra)
 iLBC (iLBC 20 (desktop), iLBC 30)
 GSM FR
 VP8 (video codec)
 H.264 (video codec)
 Echo cancellation, Adaptive Jitter Buffer, Packet Loss Concealment, Auto Gain Control, Noise reduction
 Codec priority settings and Codec settings per User or per account

Advanced network features*
 Network statistics
 Network handover
 IPv6
 DNS SRV

Audio, video & chat functionalities
 Audio calls, hold, mute, call waiting *
 Call conference *
 Call recording
 Call transfer *
 Video conference
 SMS/IM
 Presence

Contact management features*
 Contact list import
 Instant contact search
 Instant adding of contacts
 Avatars per contact

Interface features
 Multilanguage support: English & French*
 Optional auto-pop-up-window on incoming call*
 Always on top, Minimize on start-up, etc.*

Integration tools:
 API, Auto-provisioning (HTTP, HTTPS, SFTP and FTP)*

CRM integration (click-to-dial): OPTIONAL
 Vicidial
 CallPro
 Nimble
 Freshdesk
 SalesForce

Customization:
 Custom logo, Branding, etc.